TIP TIG Welding is always better quality than TIG and 100 to 500% faster with superior quality than TIG - MIG - FCAW.

ALL WELDS SHOULD FIRST BE PRE-QUALIFIED BEFORE
THE WELD PROCEDURES ARE APPROVED.

HPS. High Performance "Weathering Steels".

High-Yield-strength steels. (HY-steels.)

SMAW and GMAW Mechanical Strength
E6010 Minimum Yield 50,000 psi Minimum Tensile 62,000 psi.
E6011 Minimum Yield 50,000 psi Minimum Tensile 62,000 psi.
E7010 Minimum Yield 60,000 psi Minimum Tensile 72,000 psi.
E7018 Minimum Yield 60,000 psi Minimum Tensile 72,000 psi.

MIG E70S-3-6 Minimum Yield 60,000 psi Minimum Tensile 72,000 psi.

Mechanical Strength of Gas Shielded Flux Cored Electrodes from the
ANSI / AWS A5.29. 1198 Specification
Low Alloy Steel Electrodes for Flux Cored Arc Welding

Brittleness? The ease at which the weld or metal will break or crack without appreciable deformation. When a metal gets harder it becomes more brittle. Preheat, inter-pass temp controls and post heat all are designed to reduce the potential for brittleness.

Welding alloy steels often may require unique weld or heat treat considerations. Compare the low alloy steels chemistry and mechanicals with a standard A36 steel. Remember this site is only a guide, weld responsibility starts with "you" and the development of a PQR.

 

The "yield strength". The stress that can be applied to a base metal or weld without "permanent deformation" of the metal.

The "tensile strength". The ultimate tensile strength, the maximum tensile strength that the metal or weld can with stand before "failure occurs".

Metric Conversion 1000 psi = ksi x 6.894 = MPa

AISI SAE DATA AS A GUIDE FOR WELDING ONLY. ALL WELDS REQUIRE PRE-QUALIFICATION. NOMINAL ALLOY CONTENT MAY BE PROVIDED, (NOT VERIFIED).

 

AISI steels. When selecting electrodes take note of;
[a] the carbon content and the primary alloys.
[b] Over 0.03 carbon ensure low hydrogen electrodes.
[c] Over 0.35% carbon give SPECIAL consideration to pre-heat / inter-pass temp control and post heat.

THE FOLLOWING IS A RANDOM SELECTION OF AISI STEELS. THE DATA PROVIDED IS TO ASSIST WITH YOUR WELDING DECISIONS. TAKE NOTE OF THE PRIMARY ALLOYS THE CARBON CONTENT AND THEIR RELATIONSHIP BETWEEN THE PRE AND POST HEAT RECOMMENDATIONS.

Weld Procedures intended for weld repairs on AISI 1040 - 1045 - 1050, forged steel components. The intention of these weld repairs is to repair cracks, surface scratches or indentations. With the low hydrogen SMAW (stick) weld process the following recommendations apply. If cracks occur clean area with grinding or a wire wheel. Drill two 1/8 (3mm) holes within 1/16 (1.6mm) of the weld crack start / stop. Pre-heat and inter pass temp control is critical to slow down the weld cooling rate to reduce the hardening effect in the welds and heat affected zone. For these high carbon steels, a minimum preheat and inter-pass temperature of 600 to 700F is required. Provide this high preheat with a "propane or natural gas " torch, do not use acetylene as its conentrated and localized. Provide the preheat on the general area surrounding the weld repair. Use a temp stick to measure the preheat. Measure the temp at least 3 to 4 inches from either side of the weld.

 

AISI 1040 - 1045 - 1050. SMAW Electrode Guide Lines:

Use an E7018 low hydrogen electrode. Polarity DC Reverse Polarity (electrode positive) or AC. If cracking occurs with the E7018 consider an E312 stainless wire, or the use of MIG short circuit. Only use SMAW electrodes if they are new and in a sealed sealed container. Use a small electrode diameter to minimize the required weld current and heat input. 1/8 or 5/32. No arc strikes are allowed on the part surface, use a scrap strike plate to establish an arc. Once electrode is warm its easier to start on shaft. Use stringer, small beads, no weld weaves. At weld completion gently peen weld bead surface with pointed end of slag hammer to assist in stress reduction. Maintain preheat during weld. At weld completion wrap insulated blanket around weld to allow slow controlled cool without drafts to shaft.

ELECTRODE E7018 DCRP 1/8 130 - 140 AMPS, first choice.
ELECTRODE E7018 DCRP 5/32 140 - 160 AMPS second choice.

If the weld draws lubricant from the shaft and creates a porous weld, grind out weld, preheat and weld again. After the weld is complete, cooled and ground, test weld surface area with dye pen.

MIG Alternative procedures.If crack issues occur with SMAW on the high carbon steels, consider MIG short circuit which provides lower weld energy. For the short circuit welds, use an E70S-3 or E70S-6 wire, size 0.035. Use argon with - 15 to 25%% CO2. Set the 0.035 short circuit wire feed at 280 ipm, around 11 0'clock. You can measure the wire ipm by the wire length attained for 10 sec. Set the short circuit weld voltage at 17 to 18 volts, and achieve crisp, consistent crisp crackle. Use stinger beads and use the preheat and other applicable weld data from SMAW procedure.

 

AISI SPECIFICATIONS

Note on 4140. If no post heat treat I would use the ESAB Dual Shield 11-70T- 12HR with Argon 25 CO2. Or the Dual Shield 11-71 Ultra if using straight CO2. Note High pre-heat / interpass required, 550 - 650F. Use blanket for slow cooling. Parts less than one inch, < 25 mm use 0.045 wire. Parts over 25 mm I i would use the 052 wire

Ultrahigh-Strength Steels are commercial structural steels capable of a minimum yield strength of 1,380 MPa (200 ksi).Three types of these steels are;

[1] Medium carbon, low alloy,
[2] medium alloy, air hardening,
[3] Hgh alloy, hardenable steels.

The common medium carbon low-alloy steels, such as 4130, 4140, 4340, and 8640, generally are supplied by the mill in either the normalized and tempered or annealed condition and are readily forged. Alloy 4130 is a water-hardening alloy steel of low to intermediate hardenability. Because 4130 steel has low hardenability, section thickness must be considered when heat treating to high hardness or strength.

E-Mail Feb 2007.

Hi Ed. Would you offer some advice on welding 4130 plate and tubing using GMAW? I have looked in the books that we have of yours and have searched the discussion group and didn’t find similar enough situations for reference. The weldment consists of 4130 sheet/plate and pipe that is heat treated to 125-145 KSI ultimate tensile strength prior to welding. The sheet/plates range from .125”-.625” thick and the tubes range from .188”-.250” wall thickness. I will be using a 120 KSI UTS filler metal and the weldment will be post weld stress relieved. Do you have any suggestions on the parameters and techniques that should be applied? Thanks, Steve


From Mike. Why not use a 4130 filler metal. I have been involved with welding a structural component for the last four years. We have had excellent results. The base metal is supplied in the annealed condition. The component is pre-heated to 400F and then subjected to post weld hest treatment. In a few instances, due to engineering changes after the pwht, some minor welds were made and a local pwht was applied.

From Ed. Steve welding with or without heat treatment, its logical to use low end parameters, use stringers, avoid weaves and maintain an interpass temp of 300F max.

Manganese Steel is sometimes called "austenitic manganese steel" because of it's metallurgical structure. This steel is also called Hadfield manganese steel after its inventor. Manganese steel is an extremely tough, nonmagnetic alloy with extremely high tensile strength and a high percentage of ductility This steel has excellent wear resistance and a high resistance to impact.

Note: Manganese steel is almost impossible to machine.

Manganese steel is widely used as castings and also available as rolled shapes. Manganese steel is often used for impact wear resistance applications such as railroad components, steel mill parts and parts on equipment in quarries.

The composition of austenitic manganese is from 12-14% manganese and 1-1.4% carbon. The composition of cast manganese steel would be 12% manganese and 1.2% carbon. Nickel is oftentimes added to the composition of the rolled manganese steel.

To attain the material toughness of the manganese steel, a special heat treatment of 1850°F (1008°C) followed by quenching in water is required. To have minimal impact on the steels properties, special attention is required for welding or heating. Manganese steel can be welded to itself or to carbon and alloy steels. Clad weld deposits can be made on manganese steels.

Manganese steel can be cut with oxy-fuel cutting, keep the base metal as cool as possible. If the mass of the part to be cut is large its doubtful the heat build will cause embrittlement. If the parts to ber cut are thin, it's recommended the parts be cooled or partially submerged in water during the flame cutting operation. For removal of defects or cracks in the manganese part, the air gouging process can be used. While doing repairs, again the base metal must be kept cool. Grinding should be used to smooth up the surfaces for welds.

MANGANESE ELECTRODE 1. There are two types of manganese steel electrodes available. Both are similar in analysis to the base metal but with the addition of elements which maintain the toughness of the weld deposit without quenching. The EFeMn-A electrode is known as the nickel manganese electrode and contains from 3-5% nickel in addition to the 12-14% manganese. The carbon is lower than normal manganese ranging from 0.50 to 0.90%. The weld deposits of this electrode on large manganese castings will result in a tough deposit due to the rapid cooling of the weld metal. The manganese nickel steel is more often used as a buildup deposit to maintain the characteristics of manganese steel when surfacing is required.

 

MANGANESE ELECTRODE 2. The other electrode used is a molybdenum-manganese steel type EFeMn-B. This electrode contains 0.6-1.4% molybdenum instead of the nickel. This electrode is less often used for repair welding of manganese steel or for joining manganese steel itself or to carbon steel.

MANGANESE ELECTRODE 3. Stainless steel electrodes can also be used for welding manganese steels and for welding them to carbon and low-alloy steels. The 18-8 chrome-nickel types are popular; however, in some cases when welding to alloy steels the 29-9 nickel is sometimes used. These electrodes are considerably more expensive than the manganese steel electrode and for this reason are not popular.

STRESS RELIEVING:

STRESS RELIEF - CONTROLLED HEATING & COOLING TO REDUCE STRESSES.
STRESS RELIEF MACHINED PARTS FOR DIMENSIONAL STABILITY.
STRESS RELIEF SLOW HEATING AND COOLING REQUIRED
CONFIRM WITH CODE SPECIFICAIONS FOR STRESS RELIEF REQUIREMENTS.

 

Free Machining Steels.The term "free machining" can apply to many metals but is normally associated with steel and brass. Free machining is the property that makes machining easy because small cutting chips are formed. This characteristic is given to steel by sulfur and in some cases by lead. It is given to brass by lead.

Sulfur and lead are not considered alloying elements. In general, they are considered impurities in the steel. The specifications for steel show a maximum amount of sulfur as 0.040% with the actual sulfur content running lower, in the neighborhood of 0.030%. Lead is usually not mentioned in steel specifications since it is not expected and is considered a "tramp" element. Lead is sometimes purposely added to steel to give it free-machining properties.

Free-machining steels are usually specified for parts that require a considerable amount of machine tool work. The addition of the sulfur makes the steel easier to turn, drill, mill, etc., even though the hardness is the same as a steel of the same composition without the sulfur. The sulfur content of free-machining steels will range from 0.07-0.12% as high as 0.24-0.33%. The amount of sulfur is specified in the AISI or other specifications for carbon steels. Sulfur is not added to any of the alloy steels. Leaded grades comparable to 12L14 and 11L18 are available.

Unless the correct welding procedure is used, the weld deposits on free-machining steel will always be porous and will not provide properties normally expected of a steel of the analysis but without the sulfur or lead.

The basis for establishing a welding procedure for free-machining steels is the same as that required for carbon steels of the same analysis. These steels usually run from 0.010% carbon to as high as 1.0% carbon. They may also contain manganese ranging from 0.30% to as high as 1.65%. Therefore, the procedure is based on these elements. If the steels are free-machining and contain a high percentage of sulfur the only change in procedure is to change to a low-hydrogen type weld deposit.

In the case of shielded metal arc welding this means the use of low-hydrogen type electrode such as EXXX8 classification. In the case of gas metal arc welding or flux-cored arc welding the same type of filler metal is specified as is normally used since these are no-hydrogen welding processes.

Submerged arc welding would not normally be used on free-machining steels. Gas tungsten arc welding is not normally used since free-machining steels are used in thicker sections which are not usually welded with the GTAW process.

For the worlds best MIG and flux cored weld
process control training resources vist here.

Fatigue.The ability of a metal or weld to withstand repeated loads. Fatigue failures occur at stress levels less than the metal or weld yield strength. Some things that can influence fatigue failure:



Excess weld profiles.
Welds which cause undercut.
FCAW or SMAW slag inclusions.
Lack of weld penetration.
Excess weld heat, typically from multi-pass welds without inter-pass temp controls.
Items to a part that adds restraint while welding.
Items added to a part that can concentrate stresses in a specific location.
Incorrect selection of filler metal, weld too weak or weld too strong.|

AISI / SAE 44XX TO 98XX STEELS.
Steels	Yield  ksi  MPa	Tensile  ksi MPa	Description	Preheat Post heat	UNS	Chemistry weld data
AISI/SAE 44XX			Moly Steel	4419 preheat >13mm 100F .>25mm 200F 4419/4422/4427 post heat required FOR 4419/4422/4427 at 1200-1350F		SAE 4419 carb 0.18-0.23 Mn 0.45-0.65 Si 0.15-0.3 Mo0.45 - 0.6
AISI/SAE 46XX	4620 53-55	4620 75-85	Ni-Moly	4615 - 4617- 4620 preheat >13mm 200F >25 mm 250 F post heat desirable 1100-1250F		4615 carb 0.12-0.18 Mn 0.4/0.65 Si 0.3 Ni 1.65/2 Mo 0.2/0.3 weld 4620 E8018-C1 E80S-D2 E81T1-Ni2
AISI/SAE 47XX			Ni - Cr - Mo			carb 0.16-0.22 Ni 0.9-1.2 Cr0.35-0.55 Mo 0.15/0.4
AISI/SAE 48XX			Ni- Mo			carb 0.13-0.23 Ni 3.25-3.75 Mo 0.2 /0.3
AISI/SAE 50XX			Carb/Chrome	AISI 5046 preheat <13mm 300 F <25MM 350F >25mm 400F		50xx range carb 0.12-0.48 Mn 0.3/1 Si 0.15-0.35 Cr 0.2-0.6
AISI/SAE 51XX			Carb/Chrome HIGHER CHROME THAN 50XX	AISI 5120 E8016-B2 E80T1-B2 >13mm 250F post heat desirable 1100 to 1250F		51xx range carb 0.13-0.53 Mn 0.6/0.9 Si 0.15-0.35 Cr 0.7-1.15
AISI/SAE 61XX			Cr / V			carb 0.16-0.54 Mn 0.5/0.9 Cr 0.5-1.15 V 0.1-0.15
AISI/SAE 81XX			Ni / Cr / Mo			carb 0.13-0.18 Ni 0.2/0.4 Mo.0.08-0.15 Cr 0.3-0.5
AISI/SAE 86XX			Ni Cr Mo			carb 0.12 / 0.48 Ni 0.4/0.7 Mo.0.15-0.25 Cr 0.35-0.6
AISI/SAE 87XX			Ni Cr Mo			carb 0.18-0.46 Ni 0.4/0.7 Mo.0.2-0.3 Cr 0.35-0.6
AISI/SAE 88XX			Ni Cr Mo			carb 0.2-0.25 Ni 0.4/0.7 Mo.0.3-0.4 Cr 0.4-0.6
AISI/SAE 93XX			Ni Cr Mo			Ni 3.25 Cr 1.2 Mo 0.12
AISI/SAE 94XX			Ni Cr Mo			Ni 0.45 Cr 0.4 Mo 0.12
AISI/SAE 97XX AISI/SAE 98 XX			Ni Cr Mo			Ni 0.55 Cr 0.2 Mo 0.2 Ni 1 Cr 0.8 Mo 0.25

AISI SAE HIGH STRENGTH SHEET STEEL DESIGNATIONS:

AISI 035SF. First three digits = minimum yield 35 ksi (241 MPa)
035SF First letter after numbers denotes chemistry composition

(S) = structural quality C-Mn-p-n,
(X) = low alloy Cb-Ti-V-Si-Zr
(W) = weathering steels Si-P-Cu-Ni-Cr
(D) = Dual phase Matensite transformation

AISI 035SF Last letter denotes deoxidation practice. (F) Deoxidation Killed Steel Inclusion control. (K) Deoxidation killed steel. (O) Deoxidation is none killed. To find heat treat, chemistry and weld data cross reference these steels with the following ASTM Steels. Go back to the steels program home page to find your ASTM steel.

 

Silicon Steels or electrical steels, are steels that contain from 0.5% to almost 5% silicon but with low carbon and low sulfur and phosphorous. These steels are provided as sheet or strip and used frequently in punched or stamped applications such as laminations for electrical machinery.The silicon steels are designed to have lower hysteresis and eddy current losses than plain steel when used in magnetic circuits.

Silicon steel stampings are used in the laminations of electric motor armatures, rotors, and generators. They are widely used in transformers for the electrical power industry and for transformers, chokes, and other components in the electronics industry.

For the laminations welds, the welds are made on the edge of each sheet to hold the stack together. Almost all of the arc welding processes are used, MIG, submerged arc, shielded metal arc, gas metal arc, gas tungsten arc and plasma arc welding. When the consumable electrode processes are used the stampings are usually indented to allow for deposition of filler metal. For gas tungsten arc and plasma arc the filler metals are frequently not used and the edges are simply fused. The size of the weld bead should be kept at minimum so that eddy currents are not conducted between laminations in the electrical stack.

One precaution that should be taken in welding silicon steel laminations is to make sure that the laminations are tightly pressed together and that all of the oil used for protection and used in manufacturing is at a minimum. Oil can cause porosity in the welds which might be detrimental to the lamination assembly.

 

Hardness?
The resistance of the metal or the weld to penetration. Hardness is related to the strength of the metal. A good way to test a weld after the weld and heat treatment are complete, is to test the hardness of weld and the base metal surrounding the weld.

Ductility?
The amount that a metal or weld will deform without breaking. Measured on welds by the % of elongation in a 2 inch 51 mm test piece. An E71T-1 flux cored electrode should result in a minimum of 20% elongation. An E70S--6 MIG weld should produce approx 22%.

Toughness?
The ability of the metal or weld sample at a predetermined temperature to withstand a shock. The test for toughness measures the impact of a pendulum on a notched specimen. You may see that the required impact properties for the metal or weld are 20ft-lbf @ -20 F (27 j @ -29C)

If you are welding a carbon steel and you don't know what the composition is or what the weld consumable should be, try the following:

• If the metal is thicker than 6 mm preheat to 150F.
• Use either an E7018 stick electrode, an 0.035 or 0.045 E70S-6 MIG wire. For your all position welds an E71T-1 electrode wire.
• For MIG welding use an argon 10 to 15% CO2 mix.
• For flux cored use a mix with 20 to 25% CO2.
• Ensure with multi-pass welds you use inter-pass temp control. Ensure the inter-pass temp weld temperature does not exceed 200F.
• If possible do destructive test of a weld sample.
• If possible have the hardness and grain size checked after welding.

  
  
  
  
  Abrasion-Resisting Steel (AR).
  Typically AR steel is not used for structural applications. AR steel is a high carbon steel typically used for wear resisiting components such as material-moving equipment and dump truck liners and for components where severe abrasion and hard materials are used. Most AR steels have a 0.80-0.90% carbon range; however there are low carbon AR steels with multiple alloying elements.

The AR steels are very strong with a hardness of approx. 40 HRc or 375 BHN. AR plates are typically welded to the structures they are designed to protect and once worn removed by oxy / fuel cutting or carbon arc.

When welding AR steels, the low-hydrogen weld processes are required. A preheat of 400°F is used to avoid underbead cracking of the base metal or cracking inthe weld. During cold weather ensure the AR steels have a minimum temp 100°F (38°C) temperature prior to welding. On some applications, the 400F pre-heat can be avoided by using a "preheat weld bead" on the carbon steel structure close to the AR steel and then filling in between the pre-heat bead and the abrasion-resisting steel with a second bead in the groove provided. The first bead on the regular carbon steel should locally preheat the AR steel and the second bead is made to join the regular steel to the AR steel. Intermittent welds are usually made since full-length welds are usually not required. Avoid deep weld fusion into the AR steel to minimize carbon pickup in the weld which can increase the crack potential.

When welding AR steels, you can use SMAW the E-XXX8 electrodes, MIG or flux cored. When using MIG spray, use low penetrating shielding gases such as argon - 10% CO2 or argon - 2% oxygen. Use the lowest current with gas shielded flux cored or use straight polarity self shielded flux cored which minimizes deep weld penetration.

 

Dual - Ten Stl manufactured by US Steel

 

Dual TEN are dual phase steels with a mix of ferrite matrix and martensite islands decorating grain boundaries with possible addition of bainite. These steels contain approx. 5 - 15% martensite. These steels therefore offer that unique combination of Ferrite = soft phase (ductility) and martensite = hard phase offering high strength.

Grades Dual Ten 590 / 600

Grades Dual Ten 780 / 800

Dual Ten Strength UTS 72 - 175 ksi 500 - 1200 Mpa

Dual Ten high rate of work hardening

Dual Ten offer weigh reduction even in comparison to high strength steels, this means the auto industry will embrace them and you will be welding parts less than 1.2 mm thick For more information on the unique mechanical properties of this steel vist the US Steel site.

The only information on welding i found at US STEEL on welding, is that these steels meet auto application weld needs. From my perspectice, Its logical with these steels to minimize weld heat input, so short circuit or high weld speeds with the open arc modes of weld transfer would be logical.. No pre-heat on gage and definately look to interpass temp controls, at a guess i would state 200F.

 

Use Em's process control resources to provide
optimum MIG - FCAW PQR's and weld procedures.

Return to www.weldreality.com Welding home page.