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Welcome to the world's largest web site on MIG (GMAW) welding. This program eliminates the sales induced gas ignorance and misleading information that for decades has surrounded MIG gas selection.

This web site was first established in 1998 by Ed Craig. Contact Ed (now Em) . ecraig@weldreality.com

 


MIG Gas information. Section 1.


Five decades of sales nonesense and lack of weld shop MIG weld process control expertise has for many made a joke out of MIG Gas Mix Selection.

On the subject of the common MIG gas salesmanship, gas hype and process ignorance that typically saturates MIG gas mix information and selection and leaves the global weld industry with ten times the amount of MIG weld gas mixes required, please remember, that when it comes to getting advice from most industrial gas companies, that a MIG weld BS lie when told often enough, will eventually becomes a weld shop truth. Ed / Em Craig:

Note: I was one of the key writers that wrote MIG Shielding Gas specification. AWS A5.32 for the American Weld Society, and also at one time or another I worked in the roles of weld training / product manager with Linde (Praxair), Liquid Air, Air Gas, AGA, and Liquid Carbonic.

MIG GAS FACT: Whenever you see a new "three" or four part gas mix for MIG welding carbon or any alloy steels, you know the gas manufacturing marketing team and sales team is doing their thing as they have done for decades with the introduction of another, useless over priced MIG gas mix.

MIG GAS FACT: If you worked for a company that in the last three or four decades was using any three part gas mixes, or argon - 25% CO2 for steels and alloy steels MIG welds, you were working for a management and weld shop that had no clue about the MIG weld process requirements.

MIG GAS FACT: For decades the worlds leading MIG weld equipment manufactures such as Lincoln, Miller and ESAB followed the gas companies marketing influenced BS recommendations, this simply adding to the MIG gas process misinformation, lies and confusion which sadly for more than 5 decades has been imbedded throughout most (not all) of the global MIG weld industry.

MIG GAS FACT: A MIG Weld Gas Reality: In a thirty minute practical weld demonstration, I could as anyone should with MIG weld process control expertise, demonstrate that all the over priced, global three part gas mixes being used for MIG welds on carbon steels, stainless and alloy applications, provide no practical MIG weld quality, metallurgical or weld production benefits.


MIG GAS FACT: So your company is working to some AWS spec. Be aware that too often the AWS weld process and consumable specification committees were made up of weld consumable / equipment "marketing / sales" individuals. These characters too often bought process myths and product bias influence into the formation of the weld specifications they are working on.

Note A good portion of my efforts at the AWS MIG gas spec. meetings was trying to minimize the extensive sales hype and BS that some of the gas committee members wanted to introduce into the important AWS MIG gas specification. AWS
A5.32 specification.

 

MIG GAS CONFUSION HELPS CREATE GAS COMPANY & DISTRIBUTOR PROFITS:

With over 40 different MIG gas mixes, (the weld industry needs no more than 4) and the approx. five decades of global, MIG gas mix confusion, has been very beneficial for the global industrial gas companies / distributors weld gas sales and ptofit margins.

 

So to increase our MIG gas profit margins & help us get into a competive gas accounts,
Ive come up with a new three part gas mix for steel MIG welds, lets call it "BS" gas.


Note: Some of the gas information on this web site is taken from my MIG and flux cored weld process controls - Best Weld Practice, Self Teaching - Training Resources.

WELD SHOP MIG PROCESS IGNORANCE GOES ALONG WAY TO ENABLING GAS MARKETING BS: When the gas company promotes it's commodity gas product in an industry where MIG weld process and consumable ignorance and confusion is too often the norm, that gas company marketing department is provided with the opportunity to provide extensive MIG gas mix bovine fecal matter, (in reality the majority of gas company executives involved with MIG gas mix sales simply do not have a clue about the MIG weld process, and the energy and reactivity conserns of the MIG gas selected. All most gas companies typically care about is increasing their industrial gas mix commodity prices and increasing their their customer base.

 


2019: ITS NOT JUST THE GLOBAL GAS COMPANIES, THE WELD DISTRIBUTORS OR THE MIG EQUIPMENT MFGs THAT FOR DECADED HAVE ADDED TO THE MIG GAS CONFUSION, ITS ALSO THE FAILURE OF THE FACILIIES THAT TRAIN WELD PERSONNEL AND ENGINEERS, ALONG WITH THE SAD GLOBAL WELD SHOP LACK OF MIG WELD PROCESS CONTROL EXPERTISE THAT HAS ENABLED THE COMMON MIG WELD GAS MYTHS AND CONFUSION TO BE THE NORM:

 

-

Well if they get that exited about our new 3 part gas mix for steels, why not give them a four part mix?


WITH TRADITIONAL CV MIG EQUIPMENT, FOR DECADES THIS HELIUM TRI-MIX PRODUCT INTRODUCED BY UNION CARBIDE / Linde IN THE 1960s, IS SIMPLY A MIG GAS PRODUCT THATS NEVER BEEN NECESSARY FOR STAINLESS STEELS WELDS.

TRI-MIX: 90% HELIUM - 7. 5% ARGON - 2.5% CO2:

The weld industry would be better served learning MIG weld process control expertise instead of talking to a saleman who likely has never ran a weld shop.


THE 90% HELIUM TRI MIX GAS FACT: For decades and still today in 2019, thanks to 1960s Union Carbide, (Linde), many North American and European weld shops purchased this Helium tri-mix for MIG welds on stainless gage applications. The helium tri-mix was in reality the worst possible gas mix choice for most gauge stainless steels.

MIG GAS MIX WELD REALITY. With most MIG stainless gage (<3mm) weld applications, three primary MIG weld concerns in most weld shops when welding THIN GAUGE STAINLESS parts would typically be;

[1] MIG weld burn through,
[2] MIG weld part distortion,
[3] MIG weld oxidation.

AND THE COMMON DENOMINATOR OF 1 - 2 - 3 IS?

The above MIG weld issues are common for stainless thin gage MIG applications, and I dont believe that it should take much to figure out with the above three primary MIG stainless gauge weld issues that the common denominator is the weld issues are all "WELD HEAT RELATED" .

The Union Carbide (Linde) MIG gas solution for their stainless gage customers who often were dealing with weld heat related issues, was to promote and sell the worlds "HOTTEST MIG gas mix", a tri-mix containing 90% helium - 7.5% Argon - 2.5% CO2. This is a gas mix requires the highest MIG weld voltages, this is a mix that puts more energy into a MIG weld than any of the other available MIG gas mixes.

Note: In the 1980s, while working for AGA as the US corporate weld training manger. twenty plus years after the Carbide / Linde introduction of the Helium tri-mix, I was determined to do my best to try and reduce the stainless gas MIX BS data which was common with both carbon steels and alloy steels.

I set to MIG welding 20 to 10 gauge stainless MIG weld samples, (butts - flillets - lap welds). Optimum MIG parameters to me are like breathing, so using the best possible short circuit weld parameters for the gauge and joint type welded, I evaluated several MIG gas mixes including the Helium Tri-mix with focus on the weld energy suitability to the common stainless gauge sizes used. And to make a long story short, in the 1980s, I developed and introduced a new Stainless TWO PART Gas Mix that would provide real world MIG weld solutions for all Stainless, Duplex & most other Alloy steels, that gas mix was 98% Argon - 2% CO2
.


Ed now Em's developed the practical and cost effective two part MIG gas mix. 98% Ar - 2% CO2. If you are using this gas mix there is no need for thanks, but you can send a case of wine,


To reduce the weld heat related weld issues on stainless gauge applications, Em while at AGA located in Cleveland, took the ninety percent helium out of the widely utilized helium Tri mix 90% He - 7.5% Ar - 2.5% CO2 stainless mix. And she changed the ridiculous tri-mix CO2 content from 2.5% C02 to 2% CO2.

In the 1980s Ed / Em created the 98% Ar - 2% C02 mix which AGA US was delighted with and then AGA introduced this gas mix to N. America.


 

SO LETS GET TO WHY THE HELIUM TRI GAS WAS DEVELOPED: Long ago, when TV sets in England were mostly black and white, and at least 25 years before the introduction of pulsed MIG equipment, Union Carbide / Linde, a highly reputable, typically no BS global leader in producing everything related to MIG, established a gas research project on the influence of MIG gas mixes on stainless welds. The research engineers examined Helium and out of the gas research they developed the Helium MIG tri-mix, 90% He - 7.5% Ar - 2,5% CO2 and they saw this gas mix as a solution for short circuit MIG welds on stainless gauage applications.

What most people in global weld shops, would not realize was that the Union Carbide / Linde MIG gas mix researches developed and tested their Helium Tri-mix to improve Short Circuit (SC) welds on
THICK GAUAGE STAINLESS PARTS > 0.100.


As most of us around stanless MIG short circuit welds are aware, stainless with its high alloy content has a slower weld solidification rate (sluggish welds) than common carbon stees. With the low low voltages & current thats utilized with the short circuit weld transfer mode, short circuit welds on the thicker gauges would often produce convex gage welds (evident freeze lines) that could reveal poor weld fusion.

The extra weld energy that helium provided for the thick gauge, short circuit stainless welds came mostly from the higher SC weld voltage requirements with helium, (1 to 3 volts typical), and so this gas mix was viewed as a solution for all stainless gauge short circuit welds.


HELIUM TRI-MIX MIG WELD FACT: The reality in the 1960s Union Carbide / Linde helium tri-mix research, was that all the common MIG weld transfer modes and process control options were not included in the MIG stainless thick gauge weld research. And therefore from a weld process logic, the tri-gas mix research was very incomplete and therefore the results were misleading.

In the 1960s, with the rapid growth of MIG, Carbide / Linde was providing excellent MIG, flux Cored and SAW data with minimum BS. However in this time period MIG equipment sales were explosive and weld shops as they are today showed little interest in process expertise, so if the gas companies and Linde Miller or Licoln made a statement on a weld process requirement, well it must be real, right?

ANY WELD RESEARCH WILL ONLY BE AS GOOD AS THE WELD APPLICATION / PROCESS EXPERIENCE OF THOSE DOING THE RESEARCH: As with many weld research projects in the 1960s when MIG was still a relatively new process, those working in research labs may have lacked either weld process control or wide weld application expertise. As for the MIG gas products that have come to weld shops in the last two to three decades, well to use the word "research" for MIG gas mix development would be more than generous.

The new Helium TRI-MIX in the 1960s was seen by Carbide / Linde marketing personnel as a good sales tool to get their distributors access into the numerous global MIG accounts that were using short circuit and welding stainless. As that time of the tri-mix introduction, and also ironically 70 years later, weld shops played around with MIG controls and if Linde said this was the best gas mix, in an industry that placed little value on weld process control expertise, who was going to argue?

Remember Union Carbide / Linde was considered the best technical leader in their development of industrial MIG weld gases, weld wires and MIG equipment. Their Helium Tri Mix research and recommendation had a large impact on the global weld industry. The resulting helium Tri-Mix gas sales were extensive, and the reality set in for Carbide and also for other gas companies that the introduction of three part gas mixes, was a good marketing tool to attain new gas, wires and weld equipment business, a good tool for market growth and increased profit margins for industrial gases.

For seven decades, most of the global weld quipment and consumable mfgs & distributors have always been looking for a so called unique weld wire, gas mix or bells and whistles MIG power source that will enable to get into a competitive weld shop account.

Apart from the common gas mix BS, most weld shops were not aware that most of the pulsed MIG equipment introduced up to 2015, provided no steels or alloy steels MIG weld benefits.


MORE ON MIG TRI-MIX AND WELD PROCESS FACTS: In the 1960s or today in 2019, the traditional CV MIG equipment enables both Short Circuit and Spray Transfer. However those Union Carbide MIG Tri mix gas researchers when doing gas research on stainless gauge welds focussed on MIG short circuit welds on > 0.100 stainless parts.

Unfortunately the gas research personnel seemed unaware of utilizing the low end Spray transfer parametrers with an 0.035 MIG wire was an excellant weld approach for most stainless gauge MIG welds on parts >0.100. With the higher weld deposition, Spray mode and using the common 0.035 (1 mm) wire at the "spray start parmeters" the MIG welds in contrast to short circuit would "allow much higher weld speeds". Increased weld speeds dramatically decrease weld heat related concerns and also the spray welds dramatically enabled improved weld fusion, decreased porosity and a dramatic increase the weld shop productivity.

DO YOU KNOW WHAT THE SPRAY START POINT PARAMETERS ARE WITH A STAINLESS MIG WELD AND USING AN 0.035 (1mm) WIRE? This is what my MIG and flux cored weld process controls - best weld practice self teaching - training resources provide.

THIN OR THICK STAINLESS APPLICATIONS, MY 2% CO2 MIX PROVIDES MANY MIG WELD BENEFITS.
For the weld shop, my Argon - 2% CO2 mix enabled lower weld voltages than required with the Helium Tri mixes making this gas mix better suited to welding the common "thin gauge stainless parts. As for thicker > 0.100, stainless parts, using an 0.035 (1 mm) MIG wire, and low end Spray transfer settings and you had an excellent low to moderate energy MIG Spray gas mix.

WITH ARGON 2% CO2 and knowing when to switch from Short circuit to Spray parameters, you end up with a low cost two part gas mix. And having no oxygen in the mix. the stainless argon CO2 welds would have lower weld oxidation potential, easier cleaning and less porosity.

PULSED MIG PROVIDES ANOTHER PROCESS SOLUTION FOR STAINLESS. It took more than 30 years of pulsed MIG weld equipment development and finally some pulsed MIG equipment such as built by OTC can actually provide some weld benefits for for both thin and thick stainless steel welds. So apart from short circuit and spray mode solutions for stainless welds, weld shops also have another transfer mode solution.

PULSED - SHORT CIRCUIT OR SPRAY, MY ARGON 2% CO2 GAS LOGIC STILL APPLIES: With some of the available Pulsed MIG equipment sold in 2019, you can use the pulsed mode with 0.045 (1.2mm) wire on most gage steels, stainless and alloy applications. Keep in mind that in contrast to arc on - arc off, short circuit transfer, the pulsed mode is an "open arc weld mode" with the benefits of peak current and low back ground current you can get good gage weld results and also when spray is too hot, get good weld results for welds > 0.100. However no matter what your MIG equipment choice is my gas mix Argon - 2% logic still applies.

MOST MIG EQUIPMENT AND ALS WELD WIRE Mfgs. DID NOT HAVE A CLUE ABOUT MIG GAS MIXES: Over almost the four decades that I evaluated the mostly poor performing pulsed MIG equip. it was interesting for me to watch the major MIG weld equipment manufactures while slowly make electronic improvements with their erratic and poor performing pulsed MIG units, that they would be recommending MIG gas mixes for their pulsed welds, and the mixes they would recommend would often be a poor choice often based on the usual bovine fecal matter that for decades surrounded MIG gas selection.


Lets nip back to the 1980s with AGA, while i was developing the 98% argon - 2% CO2 mix:

AGA Cleveland, was a good company to work for and they gave me much freedom for gas research. Eventually in my stainless MIG weld / gas tests, I found that the real solution to the heat related weld issues on thin stainless parts was to simply take the helium out of the helium tri-mix. That left me with Argon - 2.5% CO2. I knew that 0.5% CO2 in any mix makes minimal difference to a weld, so I ended up with a stainless gas mix that contained Argon - 2% CO2.

By the way I was well aware in the 1980s that with stainless MIG gas mixes its beneficial to keep the CO2 gas content under 5% as this minimize and chance of carbon pick up which was importants with the low carbon stainless welds.

Apart from AGA I eventually introduced my two part Argon - 2% CO2 gas mix with different North American companies such as Air Gas and Liquid Carbonic. Also I gave my argon 2 gas mix a name that would eliminate cylinder selection confusion for weld shops, I had sticker put on the cylinders and called the gas mix StainMix.
My argon - 2% CO2 mix, has been in use for more than two decades in many countries, and typical of the weld industry, I never got a thank you note from anyone who either sells it or uses it.

Argon 2% CO2 is ideal for all stainless short circuit welds with an 0.035 wire on gage parts <2.5mm. And it's also a great mix for all alloy welds with both Spray or Pulsed MIG.


E-mail: Hello Craig.

I would like to thank you for the excellent information on your website, I'm a 4th year welding engineering student at Penn College of Technology and I'm currently knee deep in my internship. With the help of your information I was able to convince management to switch from the helium tri-mix to 98% argon - 2%CO2 mix for our 300 series stainless steel MIG welds. I'm also currently running tests to demonstrate that running 100% CO2 is probably not the most economical situation for structural steel welds (3/16 angle iron). Thank you again for all the information on your site, I've been introducing your weld process control - best practice information to increase efficiency both in engineering and fabrication.



98% Argon - 2% CO2. Stainless, Duplex and most Alloy steels, Short Circuit WELD BENEFITS:

 


STAINLESS GAS FACTS: Summary of 98% Argon - 2% CO2 MIG weld benefits on alloy "gage parts":
In contrast to the higher energy and higher voltages required from a 90% helium 7.5%% Ar - 2.5% CO2 tri-mix, the much lower cost, and more gas in the cylinder, argon - 2% CO2 mix, will when short circuit or pulsed MIG welding thin gage (<2 mm) stainless;

[a] reduce weld burn through potential,
[b] reduce weld distortion potential,
[c] reduce weld oxidation potential,
[d] reduce the potential for weld cracks.
[e] reduced weld volt requirements, easier for low parameter arc stability and for more comfortable for the welder,
[f] reduce stainless weld fumes from lower weld voltage.

FOR THOSE WELD SHOPS USING THE COMMON ARGON - 2 - 5% OXYGEN MIXES FOR SPRAY WELDS:

After I finished my gas research on stainless gage parts, I then turned my gas research attention to MIG Spray Transfer on thicker stainless > 2 mm applications, (no pulsed MIG at that time). For decades most Spray stainless MIG welds were typically welded using the common Ar with 2 to 5 % oxygen mixes. Please remember when pulsed MIG was being introduced in the nineteen eighties we did not have pulsed equipment that provided consistent pulsed drop transfer and worked for two days in a row without doing something weird.


Ed = Ems Mix. 98% Argon - 2% CO2. Stainless / Duplex
and alloy steels, Pulsed and Spray Weld Benefits:



Gas mixes should be selected due to the weld transfer capabilty
and weld energy and oxidation generated.



MIG SPRAY and PULSED MIG. Stainless, Duplex and Alloy Applications > 0.100:

For more than five decades in North America and Europe, Argon 2 to 5% oxygen mixes were the most common MIG gas mixes sold for welding stainless and alloy steel SPRAY applications, which was ironic as the stainless and alloy welds required protection from the oxygen in the atmosphere.

In the 1960s or in 2020, argon oxygen mixes have always been a poor choice for any MIG welds.

In my weld gas research, for MIG welding > 0.100 stainless welds, I examined the differences between my low oxidizing Argon - 2% CO2 mix and the traditional argon 2 to 5 % oxygen mixes that were commonly used by global weld shops for spray and pulsed MIG applications.

Note: It's important to remember that one percent oxygen is approx. ten time more oxidizing than one percent CO2.


 

Argon - 2% Oxygen Spray fillet on 304 Stainless:


For decades and still today in 2019, MIG Gas manufacturers and distributors have been recommending Argon - Oxy. mixes for stainless, alloys and steels Spray and Pulsed applications. If you want to part of the real weld world, reduce the weld oxidation potential that influences weld cleanliness and porosity and produce cleaner spray and pulsed MIG stainless welds, the solition is simple try my Argon 2% CO2 mix, by the way it's been recommended in my process control training resources for at least twenty years.

ARGON 2% CO2 SPRAY & PULSED MIG WELD BENEFITS: In contrast to the traditional argon - oxy mixes, ny argon 2 % CO2 mix results in cleaner, (less oxidized) welds on stainless spray or pulsed spray applications. The weld oxide reduction from the use of an argon 2 CO2 mix is especially notable when welding stainless or alloy parts > 4 mm.

ARGON 2% CO2 SPRAY & PULSED MIG BENEFITS: In contrast to argon - oxy mixes, the argon 2% CO2 mix is very beneficial on MULTIPASS stainless welds. With multipass welds the build up of oxidation and weld surface slags can result in excess weld porosity or unacceptable inclusions. The argon 2% CO2 mix is a logical choice for MIG short circuit, pulsed or spray welds on food industry applications in which the weld surface cleanliness is important.

ARGON 2% CO2 SPRAY & PULSED MIG BENEFITS: Use spray or Pulsed on parts > 5 mm, cut a fillet weld, examine the narrow root. This profile adds to weld crack formation at the root and weld porosity entrapment in the root, then compare macro weld profile from an argon 2 CO2 mix.

Note: In contrast to argon oxy mixes, when using an argon - 2% CO2 mix, on spray or pulsed applications, that typically are > 4 mm thick, you can expect cleaner welds, however when welding thin gages such as 16 gauge, please keep in mind that most of the black or gray weld surface oxidation on the weld surface is a results from the reaction of heated thin parts with the oxygen in the atmosphere.

Note: For those considering using the Lincoln MIG STT or Miller RMD process for stainless pipe root welds, (by the way both are a poor choice see my TIP TIG section) and the gas mix recommended by the weld equipment manaufactures or others, are the Helium Tri-mix, this gas mix recommendation is so illogical that its alsmost fiunny. A pipe open root MIG weld is a weld made across a gap, so with a weld that benefits from fast freeze weld characterists there is little logic in using a helium tri-mix which is worlds hottest gas mix. Of course you should be using my argon 2 CO2 mix.

RMD and STT: And for companies like Miller in which in their Weld Application / Sales manager in the 2019 Tube and Pipe Journal article recommended for his companies modified RMD MIG process when used for stainless pipe root welds, that for best performance with the RMD consider either a, 90 % He - 7.5% Ar - 2.5% CO2 mix, or my argon 2% CO2 mix. Well this statement simply points out the lack of weld process expertise and logic which is still prevalent in 2019, and the reality is it should not be coming from a company like MIller.

 

MORE ON THE SUBJECT OF CO2 CONTENT INFLUENCE ON CARBON PICKUP USING LOW CARBON STAINLESS ELECTRODES:

Or what's good for the welding goose should be good for the welding gander. An important weld issue neglected by the suppliers of electrodes and often the persons who provide weld specifications, is an issue which should have a great influence on the so called acceptance level of CO2 in a MIG gas when used for welding "L" grade stainless.

While engineers worry about the influence of CO2 on the carbon content of a stainless weld, in contrast they often are not aware that they may be allowing the stick (SMAW) low carbon stainless electrodes to have a higher level of carbon content than the equivalent MIG electrode wires.

I read that it's difficult for the manufacturers of low carbon stainless stick electrodes to get the carbon to levels < 0.030%, which is the amount specified for the low carbon stainless MIG wires. So this electrode chemistry flexibility creates a double standard from stainless weld consumable manufacturers, and from an engineering perspective it should be consisdered unacceptable. However please note that my argon - 2% CO2 mix does not change the carbon content of a weld made with a low carbon MIG electrode
.

 

From the 1980s to 1990s: Ed - Em developed these logical real world "two part" gas mixes which were optimum for the majority of all MIG steels, stainless, alloys and aluminum applications.

Most global industrial gas companies did not want the gas competion to know what was in the cylinders they sold and this often added more confusion to the weld shop. However when i was involved with gas mix development in the 1980s 1990s, there was never weld shop gas confusion in the weld shops that purchased my companies gas mixes. I ensured that anyone could look at a cylinder and on a large stick on label identify the cylinder as either a Steelmix, Stainmix or Alummix. And then to make it easy for the MIG welders I put my simplified MIG parameters required for any weld application on another label on the cylinders.

 

For those companies that have no front office weld process ownership and believe that their welders should test that new gas mix. I will simply say this. Ask ten welders including the weld supervisor, the weld parameter difference that will occur between an argon - 20% CO2 mix and an argon - 2% oxygen mix, and I guarantee you that you will get a glazed look from 20 eyes and 10 very different answers. This is called lack of weld process control expertise and you know I have a solution for your weld shop on this important topic.

New MIG Weld Gas Reality Check.

That new MIG gas mix that every few months is wheeled into the weld shop by another distributor will often be viewed by the front office weld decision makers as another crutch that hopefully will be the solution to the daily never ending MIG weld issues in the weld shop. Of course its usually just more BS and the reality is if the weld shop management dont know what the right gas mix is, perhaps they would be

better suited to managing a donut shop.

Of course weld decision makers should understand their MIG weld process control requirements?
and influence of MIG gas mixes. Why not try this MIG Weld Gas Test:
and if you would like to learn the simple MIG process control requirements, my MIG and flux cored weld process controls - best weld practice self teaching - training resources are here.


Carbon Steels and MIG Gas Selection:

 

Spray transfer occurs on steels and stainless applications with specific argon mixes and minimum, weld amp / volt requirements. You have achieved spray when weld droplets smaller than the wire diameter and a weld stream cascade across an open arc. Depending on the spray transfer weld parameters used, the weld transfer can be single drops or comprise of a combination of both weld drops and stream of molten metal.

Pulsed Spray transfer occurs on steels and stainless with straight argon or argon mixes and specific, wide range of pulsed weld parameters. You have achieved controlled pulsed when weld droplets smaller than the wire diameter cascade, uninterrupted, (for almost three decades a rarity with most pulsed MIG equipment) across an open arc.




The spray transfer MIG Gas Myths, created by the so called welding experts.

If you had been around weld shops in the 1980s - 1990s perhaps you read an erroneous MIG gas statement somewhere that states, "you cannot get Spray transfer with argon and either - 10 - 15 - 20 or 25 % CO2 in the gas mix"

1990: Weld Reality Fact. For thirty plus years, Lincoln, Miller, BOC, Hobart, Liquid Air, Air Products, Liquid Carbonic and almost everyone else in North America who made MIG welding equipment, consumables and weld gases, all stated in either their weld books or promotional MIG literature, "that you could not get MIG spray transfer on carbon steel welds with using either more than 10 or more than 15% CO2 with any MIG electrode diameter.

The so called welding experts at the worlds largest weld equipment and consumable companies must have never worn a welding shield when evaluating gas influence on the MIG spray transfer mode. The weld reality is if you know what you are doing, with "specific wire diameters", you can get spatter free spray transfer welds with argon - 25% CO2, however why use this mix when lower CO2 provides superior transfer at "more manageable weld parameters with all wire diameters".

MIG Gas Fact: Any global weld shop that uses the 75 Ar - 25% CO2 mix, is a weld shop without weld management.



So even tho I dont recommend argon - 25% CO2, for those who doubt that with an argon mix containing 25% CO2, that spray transfer is not attainable why not put on a welding shield, after all seeing is believing and do the following

For this MIG gas test, the object is produce a 1/4, 6 mm fillet weld on >3/8 (>9mm) plate. Using a 350 amp power source or larger. Set an "0.045 (1.2mm)" MIG wire feed rate at 450 in./min (11.4m/min), or place your none digital wire feed control at the 2 o'clock position. Important, to attain spray transfer with 25% CO2, you will require a higher than normal spray transfer weld voltage, typically 32 to 36 volts is required, (make sure the power source has this capability).

The high weld voltages required for the spray mode with the 25% CO2 will produce spray transfer in which the weld droplets and stream are smaller than the wire diameter.

The prime negative attribute of using argon - 25% CO2, is the high amount of CO2 provides high energy and requires high weld voltages. The resulting high arc heat and weld heat can be uncomfortable for welders. Also with 25% CO2, the high weld fluidity that results may cause issues such as undercut, oxidization or poor weld puddle control on specific welds.

Note: With an 0.035 (1 mm) MIG wire, consistent spray transfer "is not attainable with argon - 25% CO2". Spray transfer is however attainable with all MIG wire diameters including 0.035 wiew when using argon mixes with 20% or less CO2.


THE BOTTOM LINE IS THERE IS NO NEED FOR ANY WELD SHOP TO USE THE 75 ARGON - 25% CO2 GAS MIX, AS THIS POPULAR GAS MIX HAS ALWAYS PROVIDED LESS THAN OPTIMUM WELD RESULTS FOR MOST OF THE COMMON MIG WELD APPLICATIONS.



Reducing the CO2 gas content in an argon mix to a maximum of 20% for carbon steel welds, brings the spary transition current down and also brings the required spray welding voltages down to comfortable weld levels in which the welder can typically use 25 to 32 weld volts for spray transfer with the common 0.035 - 0.045 (1 - 1.2 mm) wires.

 

1989 or 2019. When will the MIG weld industry grow up.

 

When confusion reigns in a welding shop, everyone typically looks for a quick solution and in comes that salesman with their magician's approach to weld problems that would not occur if the weld shop had management or supervision weld process expertise.


The next picture was a gas companies MIG gas advertisement in a welding magazine.

Rather than the basic commodity product that it is, this gas company marketing department wants it's gas customers to believe that it's "MIG gas mixes are special" and will therefor provide unique weld benefits.

 

When marketing people get invoved with commodity weld products you add more BS and confusion to the weld shop.

 

Weld shops are not play grounds for children. Weld shops are places where people work hard, deal with complex problems and typically achieve small profits. Yet it was common for many of the gas companies to show their customer little respect with gas adds such as this

Once you take that cape off the cylinder, get rid of the Sales Bovine Fecal Matter what many gas companies did not want their weld customers to know was that MIG gas mixes are nothing more than low cost commodities.

 

Providing that so called "unique" three part gas mix for carbon steel and stainless welds enables the gas manufactures and distributors to dream up glossy brochures which enable them to attain new MIG gas accounts and generate higher gas prices and profits on what should be low cost commodity products.

Build a gas plant and bingo you have access to the world's greatest free commodity "air" All the argon, oxygen and nitrogen you will ever need pulled out of the atmosphere at very low costs. All you then need is a a distribution system, a marketing manager, glossy brochures full of unfounded or exaggerated weld claims, add a few salesmen into the pot and then direct them to find thousands of gullible weld customers who will pay a premium for the three or four part gas mixes.



Its great when the products you sell are typically in abundace and often free.


Gas company executives love their annual bonuses and share holders need to see growth, so each year, the pressure is on the gas marketing guru to invent a unique new MIG gas mix composition to get the sales and justify the higher gas prices charged.


THAT NEW BOVINE FECAL MATTER GAS MIX



Carbon Steels and MIG Tri-Mix Gas Facts.


The minute you see three or part gas mixes for sale, remember there is a sucker born every minute.

 

GAS SALES HAVE DONE THEIR JOB: For the last two decades, one the most widely marketed gas mixes promoted in North America for MIG welding carbon steels, is a tri-mix containing argon - 5 - 10% CO2 and 1-2% O2.


3 Part Gas Mixes for "carbon steels" and MIG Weld Reality.

Up to the end of the nineteen eighties, the industrial gas marketing and sales focus was placed on converting straight CO2 users to more cost effective argon mixes. With the competition for the highly profitable gas business, the two part mixes quickly turned to three part and four part mixes.

Fact: Every three and four part mix ever sold for MIG welding carbon steels and stainless offers nothing that cannot be achieved with two part gas mixes and a little MIG weld process control expertise.

In contrast to the lower cost, two part argon CO2 mixes, the three part argon - CO2 - oxy mixes used for carbon steels, offer "no practical weld benefits that can be measured" in terms of weld quality, weld metallurgy or weld productivity.


I gave the major Gas Companiestheir chance. Put Up or Shut Up.
I placed this challenge on this web site in 1999.

A challenge to any gas manufacturing company.

In contrast to a two part argon 2 - 20% CO2 mix of my selection, I believe that no gas company can show real evidence of practical, measurable, welding quality / productivity benefits from any three part "argon - CO2 - oxy" or He - Ar - CO2 gas mix when used for welding steels. If a gas company could prove it's point, I will pay $5000 to any charity of it's choice.

Its 2019 and of course the gas companies have never responded to this challenge, after all why would they want to show their deceit, ignorance and dirty laundry to their weld shop customers, and at the end of the day, the North American weld gas distributor network with it's 5000 plus salesmen is in a strong position to promote the more profitable, three or four part gas to an industry that simply does not know better.

 

Have you noticed since the introduction of three part MIG gas mixes, the lack of welding articles on this subject. Have you also noted that when some one does write an article on the cloudy, MIG weld gas subject, the author typically represent the gas company that's trying to promote the three part mystery gas product.

The gas reality of adding Oxygen to Argon CO2. Thanks to process ignorance in weld shops, gas marketing lies and salesmen that lack weld process expertise, three part mixes containing argon / CO2 / Oxy are huge sellers in North America. If you take an argon CO2 mix and add oxygen to that mix, you simply "increase the weld oxidation potential" and lower the weld energy potential .

The oxygen addition in the three part gas mixes will influence the weld root fusion profile. When you add oxy typically a narrow finger penetration profile is produced, influenced by the lower energy narrow plasma, and lower weld energy .

The narrow finger fusion weld profile freezes rapidly trapping the oxygen influenced gas oxide reactions, increasing the weld porosity potential. Remember a primary purpose of a gas mix is to prevent oxygen and nitrogen from entering the welds.



2008" Apart from the 40 years that I have evaluated MIG gas mixes, perhaps you would like another point of view. Back in the nineteen sixties, the British Welding Institute, (at that time an unbiased research organization), carried out MIG gas research. The MIG gas research indicated in contrast to argon mixes with 5 to 20% CO2, three component gas mixes containing argon - CO2 - oxygen when used for welding carbon steels "provided no practical weld benefits". The conclusion, when adding oxygen to an argon CO2 mix simply lowers the weld energy lowering the weld fusion potential increasing weld porosity potential.


Tri Mix Welding gas cost facts for steels and something your weld distributor may not tell you:

FOR DCADES, ONE OF THE POPULAR MIG GAS MIXES IN NORTH AMERICA FOR MIG WELDING CARBON STEELS, HAS BEEN A THREE PART MIG GAS MIX CONTAINING ARGON - 5 to 10% CO2 - OXY. 1 to 2%.

GAS COSTS: A THREE PART GAS MIX TYPICALLY COSTS 20 TO 50% MORE THAN A TWO COMPONENT ARGON - CO2 MIX THAT CAN GET SUPERIOR WELD RESULTS.

GAS IN THE CYLINDER: THE THREE PART MIG GAS MIXES WILL HAVE LESS GAS IN THE CYLINDER THAN A TWO PART ARGON CO2 MIX. IN CONTRAST, THE CO2 CYLINDER MIX WILL KEEP YOU RUNNING FOR AN ADDITIONAL ONE HOUR MIG ARC TIME
.

LESS WELD INTEGRITY: THE THREE PART MIXES WITH OXY ARE MORE OXIDIZING THAN MANY ARGON CO2 MIXES INCREASING THE WELD POROSITY POTENTIAL, DECREASING SIDE WALL WELD FUSION CAPABILITY AND PROVIDING LOWER IMPACT PROPERTIES.

WELD FUSION: THE THREE PART GAS MIXES WITH OXY TYPICALLY PRODUCE INFERIOR WELD FUSION, (FINGER) PENETRATION. FINGER PENETRATION LEADS TO A NARROW ROOT BAND IN WHICH THE WELD ROOT FREEZES SO RAPIDLY THAT GAS PORES MAY NOT HAVE TIME TO ESCAPE AND THIS IS A GOOD LOCATION FOR WELD CRACKS TO COMMENCE.


LESS WELD PERFORMANCE: THE THREE PART MIX WITH OXY IS MORE SENSITIVE TO WIRE STICK OUT CHANGES, MILL SCALE, COATINGS OR SURFACE CONTAMINATES. AS THE THREE PART MIX WILL TYPICALLY REQUIRE LOWER VOLTAGE, (THANKS TO THE OXY) THESE MIXES HAVE LESS ARC STABILITY WITH MANY HIGH DEPOSITION / HIGH WELD SPEED APPLICATIONS.


If you still believe a three or four part MIG gas mix is necessary for your weld applications, give me a call, I am looking for investors to buy a ferry boat business in the middle of Kansas. If you need more convincing, my 600 page "Management Guide To MIG book has more than 100 pages on MIG Gas Reality for all applications.




My 600 page book on MIG and my MIG process control training resources has all the info you need, sorry no BS included

2019. If the world's supply of oxygen was lost to the weld industry tomorrow, as it would have for the last 70 years, have zero impact on the global MIG welding industry. It would have an impact on the industrial gas suppliers.

 

THEY SELL IT BECAUSE THEY GOT IT FOR ALMOST NOTHING: In the welding industry, there has never been a need for any MIG gas mix that contains oxygen, however their has always been a great need for industrial gas companies to sell their abundant, low cost supply of oxygen and a need to annually keep their share holders happy by increasing their industrial gas margins. Ed. Craig 1991.

 

2007: ED'S MIG GAS SELECTION. SIX MIG MIXES FOR THE MAJORITY OF GLOBAL MIG APPLICATIONS.




Ed / Em developed and introduced this Gas Mix to North America in the 1980s.

Argon - 15% CO2:

Compatible mix range, 13 - 17% CO2.


A MULTIPURPOSE GAS MIX FOR MIG & GAS SHIELDED FLUX CORED FOR CARBON AND LOW ALLOY STEEL WELD APPLICATIONS:

Applications: Great?multipurpose?MIG gas mix: Use with short circuit, spray, pulsed spray modes. Also for "all position" flux cored welds on carbon steels, low alloy steels, stainless, Inconel and duplex.

From the nineteen seventies to the early nineteen nineties, argon CO2 MIG mixes were few. The two most popular mixes were argon - 8 % CO2 and argon - 25% CO2.?

Argon - 20% CO2 was a common mix sold in Europe before it was introduced by AGA in the US. Today argon 20% CO2 is a common mix also in North America, however I was aware that it's not uncommon with many gas distributors the mix composition would be poor and their customers would get more of the lower cost CO2 than the 20% requested. Many weld shops were not aware that when they asked for a cylinder with 20% CO2 they were ending up with mixes that may have had 25% or more CO2 and with this amount of CO2, optimum MIG spray transfer was not possible.

To ensure the required amount of argon for spray transfer was in the cylinders In the early 1980s, while at AGA I introduced a logical gas mix, Argon - 15% CO2. This CO2 content allowed for less opportunity for the MIG gas contents to go over 23% CO2 which affects the formation of spray transfer with an 0.035 (1mm wire. In contrast to argon - 20% CO2. This gas mix enables a slightly lower weld voltage and provides improved weld puddle control with spray applications.

An argon - 15% CO2 mix is without question a good "high energy, multipurpose gas mix" suited for most weld job shops.

The argon 15% CO2 mix provides more weld energy than the argon - 8 to 10% CO2 mixes when spray transfer is used on steels that have mill scale, primers, surface contaminates and galvanealed, galvanized / coatings.

In contrast to argon - 25% CO2 which cannot provide spray with an 0.035 wire, the argon - 15% CO2 gas mix provides stable spray with all steel and low alloy steel wire sizes.

With short circuit on gage applications < 2 mm, the argon - 15% CO2 gas mix is superior to argon 25% CO2 as it can reduce the weld burn - through potential.

The argon 15% CO2 gas mix provides optimum weld results when used with all position welds using gas shielded flux cored electrodes welding carbon steels, low alloy steels, stainless, duplex and Inconel.

The argon 15% CO2 mix is also beneficial for robot or mechanized "high speed" welds on metals? > 4mm. In contrast to three part mixes containing argon - CO2 - oxygen, argon oxygen mixes or argon <15% CO2 mixes, the higher voltages required for this mix and the higher dissociation (HIGH ENERGY) properties of CO2 assist in stabilizing the arc and provide superior weld penetration.



Argon 10% CO2.

PULSED - Spray MIG Welds and all steel and low alloy steels:
Also short circuit or pulsed on steels and alloy steels < 0.080.
Compatible gas mix range. 8 to 12% CO2.

Applications: Best low energy MIG gas mix for Spray and or "Pulsed" carbon steel and low alloy steels welds on < 7 mm components. On many robot or manual carbon steel welded parts, the weld heat from high wire feed spray or pulsed welds can cause, distortion, weld burn through or excess weld fluidity causing weld undercut or oxidation. The fact that this gas provides lower energy than higher CO2 mixes makes it beneficial for these applications.

What is really interesting about this medium energy gas mix is that its also the best choice for welding thick steels as long as the?mill scale?and other surface contaminates are removed.

When spray transfer welding horizontal fillets larger than 6 mm, or multi-pass fillet welds in which the weld heat buildup is notable, the welder is aware of the high weld fluidity. Weld fluidity increases as the CO2 content of the gas increases. Argon with 15 or 20% CO2 produces welds with more fluidity than argon with 10% CO2. So if you want improved weld control remember this point.

With this same logic, if you are using the 10% CO2 mix with the pulsed / spray process on steels > 6 mm thick and you need more weld fusion , change the gas to a higher CO2 mix such as 15 - 20% CO2 mix.



Another mix that Ed developed and introduced.

98% Argon - 2% CO2.

Stainless - Duplex and alloy steels.


Composition Range. 1.5 - 2.5% CO2.
I developed this unique stainless MIG gas mix while at AGA in the nineteen eighties. This very low oxidizing mix is suited for all MIG Short Circuit, Spray and Pulsed on all stainless / duplex and high alloy weld and clad applications.

I would also recommend this mix for anyone MIG welding very thin carbon steel and low alloy steels, gauges that are thinner than < 0.040.

Note: Do not use this mix with any flux cored wires or with GTAW applications.


When welding stainless short circuit applications, forget the common, ridiculous, more costly 90% Helium - 7.5% Argon - 2.5% CO2 tri mix. This is a premium priced gas mix that the major gas suppliers love to sell.

COMPARE WITH HELIUM TRI- MIX..In contrast to the more costly, higher energy, helium tri-mix, the argon - 2% CO2 mix when used on thin gage applications can provide;

[1] less part distortion,
[2] less weld burn through potential,
[3] less contact tip issues,
[4] improved arc stability,
[5] lower cost gas,
[6] more gas in the cylinders,
[7] less opportunity for stress corrosion cracks, hot crack, and micro cracks.

COMPARE THE TRI MIX WITH AN ARGON - OXYGEN MIX? In contrast to the argon oxygen MIG mix recommended by all the gas companies for stainless spray and pulsed applications, my argon 2% CO2 mix can result in less oxidized, cleaner MIG spray or pulsed welds with less weld porosity potential.

Note: When used for "low carbon" stainless applications, the carbon content in the weld will be acceptable with this low CO2 gas mix for all short circuit, pulsed and spray stainless applications.



Sometimes with alloys a tri mix can help.
Another MIX developed and introduced by Ed / Em.


Argon - 2% CO2 - 1% Nitrogen.

Mixing range for Nitrogen. 0.75 to 1.75%
Mixing range for CO2. 1.5 - 2.5%.

Especially suited to MIG Spray and Pulsed Duplex Applications.

I developed this special MIG mix in the early nineteen nineties. On many duplex applications, the stainless gas argon 2% CO2 mix is sufficient. However if you need to increase your duplex mechanical MIG weld properties you should try this mix.

In many instances three part mixes are nothing more than a sales tool, however when MIG welding Duplex, a touch of nitrogen in the MIG mix can be beneficial.

DUPLEX AND CO2 CONTENT: Again note the very low CO2 content, enough to stabilize without oxidation or carbon pick up concerns.


DUPLEX AND NITROGEN CONTENT: When added to a weld, a small amount of nitrogen can be a potent austenite stabilizer. The addition of nitrogen to the duplex weld / steel will promote structural hardening by a solid solution mechanism. The small nitrogen addition therefore can raise both the yield strength and ultimate strengths of the duplex without impairing toughness. The low CO2, combined with the benefits of low nitrogen content, truly make this gas mix unique.

This mix will also provide stable short circuit, pulsed and spray transfer. If you are using short circuit, STT or RMD for pipe roots, first try the stainless duplex gas listed above, (argon 2 CO2). If the Duplex root or fill pass weld mechanical properties need to be increased try this gas mix.

If more weld fluidity is need for pulsed MIG or spray transfer on fillet welds and pipe fill passes on those duplex applications welds, try the following gas mix recommended for the MIG Nickel applications

Using the flux cored wires for duplex, use the argon 18 - 25 % CO2 mixes.

It's beneficial with cylinders that contain very small amounts of a gas, if the cylinders contain dip tubes for complete gas mixing. I would order this gas mix through a specially gas supplier and ask for a certificate of composition compliance.




Another TRI MIG mix developed and introduced be Ed

59% Argon - 40%Helium - 1% CO2 for Nickel Alloys:

Mix range. CO2. 0.75 to max 1.5%.

Reduce Oxidation on sensitive Nickel welds.

Note: The low CO2 content must be carefully mixed and controlled. Order cylinders with dip tubes. Pay a little more and order this gas mix from specially gas facility to ensure the mix is correct.

I developed this very unique mix in the nineteen eighties. How many of you have read in welding literature that when MIG welding nickel alloys, the gas mix cannot utilize a reactive component like oxygen or carbon dioxide. For decades this was another one of those welding myth that had a negative impact on companies that MIG welded nickel alloy applications.


When using the recommended straight argon for Nickel applications with MIG spray or pulsed welds, the wire feed range was restricted, lack of weld fusion was common, the arc would wonder and magnetic disruptions of the arc was a regular occurrence.

Being aware of the oxidation concerns with nickel welds and the benefits of low oxidizing CO2, I decided to try very small amounts of CO2 added to argon. The 1% CO2 did not oxidize the nickel welds and provided substantial weld benefits for MIG welding nickel alloys.


NICKEL AND CO2 CONTENT: When using straight argon, to maintain arc stability the wire feed rate was restricted. The 1% CO2 addition allows for increased arc stability through improved electron transfer without concern for oxidation contamination of the weld. The 1 % CO2 enabled higher wire feed rates which provided higher current capability improving weld fusion. The higher wire feed also allows higher automated / robot weld speeds and higher weld deposition rates for the nickel alloy welds. The 1% CO2 content also dramatically improved the weld fluidity of the sluggish nickel alloy welds improving the weld fusion potential.

Nickel alloys are sensitive to magnetic fields which disturb the MIG arc. The 1% CO2 assists in arc / electron stabilization, reducing the effects of magnetic disturbances and stabilizing the pulsed or spray weld transfer. After I stabilized the Nickel welds at higher than normal wire feed rates, I needed another gas addition to promote more weld energy for superior side wall fusion. I added helium.


HELIUM CONTENT: Some MIG gas mixes with 10 to 25% helium are recommended for Nickel alloy welds, however the weld effects are minimal. If you really want to add energy and fluidity to that weld, get the helium content up to 40%. Too much helium can add to the arc instability and also reduces the arc cleaning potential. As my 40% helium mix contains 1% CO2 you won't have to worry about the arc stability which is typically an issue with argon helium mixes.

You will pay more for my mix and possibly have to order it from a company that provides special gas mixes, however with the increased wire feed rate potential and superior weld fusion, you will reduce your weld labor costs by at least 30% and dramatically reduce the weld rework required on those costly nickel alloys.

This mix is also recommended for duplex applications in which additional weld energy is required. More info on this gas mix and its use for alloy welds is available in my Management Engineers guide to MIG book.



Argon- 40% Helium for thick Alum.

ALUMINUM SPRAY OR PULSED MIG ON PARTS > 1/4 (> 6 mm).


Typically straight Argon works well on many spray and pulsed aluminum applications. When MIG welding aluminum parts thicker than 1/4, > 6 mm and improved weld fusion or less weld porosity is required, the solution is to provide additional weld energy. The addition of helium provides more weld energy. It's important not to put to much helium into the mix as you can reduce the arc stability and the cleaning action. The larger argon molecules and reverse polarity are responsible for the aluminum oxide removal, (cleaning action).

ED OPTIMIZED ROBOT AND MANUAL WELDS FOR OVER A THOUSAND COMPANIES IN 13 COUNTRIES. A FEW OF ED'S PROCESS OPTIMIZATION PROJECTS ARE.

FORD F 150 FRAMES - VOLVO CABS - CORVETTE FRAMES-
HARLEY FRAMES - NEW BEETLE SEATS AND ED ALSO ESTABLISHED?
THE ROBOT WELD DATA FOR THE WORLD'S LARGEST CATERPILLAR TRUCKS.

IF YOU ARE INTERESTED IN BECOMING A WELD PROCESS CONTROL - BEST WELD PRACTICE EXPERT, HEAD TO THIS SECTION.



At one time you likely were sitting on my welds

 

Much more Gas Mix data in part two