1、iWeldingof StainlessSteelsiiNOTE: Although care was taken in choosing and presenting the data in this guide, AWS cannot guarantee that it is error free. Further, thisguide is not intended to be an exhaustive treatment of the topic and therefore may not include all available information, particularly
2、 with respectto safety and health issues. By publishing this guide, AWS does not insure anyone using the information it contains against any liability or injuryto property or persons arising from that use.Compiled/Edited byRichard D. Campbell, P.E.Welding Solutions, Inc., Broomfield, CO 1999 by Amer
3、ican Welding Society. All rights reservedPrinted in the United States of America550 N.W. LeJeune Road, Miami, Florida 33126iiiTable of ContentsChapter 1Definitions1Chapter 2Introduction to Stainless Steels and Types of Stainless Steels.5Chapter 3Stainless Steel Filler Materials.17Chapter 4Preweld Cl
4、eaning and Preparation of Stainless Steels .41Chapter 5Welding and Cutting of Stainless Steels.43Chapter 6Postweld Cleaning of Stainless Steels65Chapter 7Heat Treatments of Stainless Steels .67Chapter 8Weld Discontinuities and Defects in Stainless Steels 71Chapter 9Stainless Steels in Welding Codes
5、and Other Standards83Chapter 10Safety and Health Considerations in Welding of Stainless Steels91References and Other Publications Available from AWS .93ivTable Page Table PageBase Metal Compositions (Chapter 2)2-1 Chemical Compositions of Typical Wrought Austenitic StainlessSteels 72-2 Chemical Comp
6、ositions of Typical Cast Austenitic Stainless Steels . 82-3 Chemical Compositions of Typical Superaustenitic Stainless Steels 92-4 Chemical Compositions of Typical Ferritic Stainless Steels . 112-5 Chemical Compositions of Typical Superferritic Stainless Steels. 122-6 Chemical Compositions of Typica
7、l Martensitic Stainless Steels. 132-7 Chemical Compositions of Typical Duplex Stainless Steels . 152-8 Chemical Compositions of Typical Precipitation-HardeningStainless Steels. 16Filler Metal/Electrode Compositions (Chapter 3)3-1 Chemical Composition Requirements for Stainless Steel ShieldedMetal Ar
8、c Welding Electrodes. 183-2 Types of Welding Current and Positions of Welding. 203-3 Chemical Composition Requirements for Bare Stainless SteelWelding Electrodes and Rods 213-4 Chemical Composition Requirements for Stainless Steel FluxCored Arc Welding and Flux Cored Gas Tungsten Arc WeldingFiller M
9、etals. 243-5 External Shielding Medium, Polarity, and Welding Process . 273-6 Chemical Composition Requirements for Stainless SteelConsumable Inserts 283-7 Recommended Filler Metals for Welding Austenitic StainlessSteels 303-8 Recommended Filler Metals for Welding Precipitation-HardeningStainless St
10、eels . 313-9 Suggested Filler Metals for Welds Between Dissimilar AusteniticStainless Steels . 323-10 Compositions of Silver Filler Metals for Brazing of Stainless Steels 333-11 Characteristics of Silver Filler Metals for Brazing of StainlessSteels 353-12 Compositions of Nickel and Cobalt Filler Met
11、als for Brazing ofStainless Steels . 373-13 Characteristics of Nickel and Cobalt Filler Metals for Brazing ofStainless Steels . 383-14 Compositions of Gold Filler Metals for Brazing of Stainless Steels. 393-15 Characteristics of Gold Filler Metals for Brazing of Stainless Steels 39Welding Processes
12、(Chapter 5)5-1 Typical Groove Weld Joint Designs for Austenitic Stainless Steels 455-2 GMAW Globular-to-Spray Transition Currents for a Variety ofElectrodes. 475-3 Typical Arc Voltages for GMAW of Various Metals . 485-4 GMAW Shielding Gases for Spray Transfer 495-5 GMAW Shielding Gases for Short Cir
13、cuiting Transfer. 50List of TablesvTable Page Table Page5-6 Typical Conditions for GMAW of Austenitic Stainless SteelUsing a Spray Arc in the Flat Position 515-7 Typical Conditions for GMAW of Austenitic Stainless SteelUsing a Short Circuiting Arc . 515-8 Typical PAW Conditions for Butt Joints in St
14、ainless Steel 525-9 Typical PAW Conditions for Welding Stainless SteelsLowAmperage. 535-10 Typical Self-Shielded FCAW Procedures for Stainless SteelsUsing Stainless Steel Electrodes 555-11 Typical Conditions for SAW Double-V-Groove Joints in StainlessSteel Plate. 575-12 ASuggested Practices for Spot
15、 Welding Stainless Steels(U.S. Customary Units) . 58BSuggested Practices for Spot Welding Stainless Steels(Metric Units) 595-13 Welding Schedules Suggested for Seam Welding Stainless Steels 605-14 Projection Welding Design Data 615-15 Manufacturing Process Data for Projection Welding StainlessSteels
16、 62Heat Treatments of Stainless Steels (Chapter 7)7-1 Typical Preheat and Postweld Heat Treatment Requirements forMartensitic Stainless Steels 677-2 Postweld Heat Treatments for Martensitic Stainless Steels . 687-3 Recommended Solution Annealing Temperatures for AusteniticStainless Steels . 687-4 Ty
17、pical Heat Treatments for Precipitation-Hardening StainlessSteels 69Welding Codes and Standards (Chapter 9)9-1 Typical Stainless Steel Base Metal P-Number, S-Number, andM-Number Categories 859-2 F-Number Groupings of Welding Electrodes and Rods forQualifications. 869-3 A-Number Classifications of St
18、ainless Steel Ferrous Weld Metalfor Procedure Qualifications 879-4 Preheat Requirements in Various Codes 889-5 Postweld Heat Treatment Requirements in Various Codes 89viFigure Page Figure PageChapter 33-1 Standard Consumable Insert Designs 29Chapter 55-1 Schematic Illustration of Weld Bead Produced
19、with Arc WeldsMade with the Same Parameters (Current, Voltage, and TravelSpeed) on Different Materials 435-2 Schematic Illustration of Distortion Produced with Arc WeldsMade with the Same Parameters (Current, Voltage and TravelSpeed) on Different Materials 435-3 Typical Welding Currents Versus Wire
20、Feed Speeds for300 Series Stainless Steel Electrodes. 465-4 FCAW Electrode Feed Rate Versus Welding Current forSelf-Shielding E308T-3 54Chapter 88-1 SensitizationFormation of Chromium Carbides at GrainBoundaries . 728-2 Weld Metal Area, Heat-Affected Zone, and Base Metal . 728-3 Multi-Pass Weld. 738
21、-4 Weld Penetration in Stainless Steels 768-5 Weld Penetration in Mismatched Base Metals. 768-6 DeLong Diagram 788-7 Schaeffler Diagram 798-8 Weld Dilution. 80List of FiguresviiBasic Safety PrecautionsBurn Protection. Molten metal, sparks, slag, and hot work surfaces areproduced by welding, cutting,
22、 and allied processes. These can cause burnsif precautionary measures are not used. Workers should wear protectiveclothing made of fire-resistant material. Pant cuffs, open pockets, or otherplaces on clothing that can catch and retain molten metal or sparks shouldnot be worn. High-top shoes or leath
23、er leggings and fire-resistant glovesshould be worn. Pant legs should be worn over the outside of high-topshoes. Helmets or hand shields that provide protection for the face, neck,and ears, and a head covering to protect the head should be used. In addi-tion, appropriate eye protection should be use
24、d.Electrical Hazards. Electric shock can kill. However, it can be avoided.Live electrical parts should not be touched. The manufacturers instructionsand recommended safe practices should be read and understood. Faultyinstallation, improper grounding, and incorrect operation and maintenanceof electri
25、cal equipment are all sources of danger.All electrical equipment and the workpiece should be grounded. The work-piece lead is not a ground lead. It is used only to complete the welding cir-cuit. A separate connection is required to ground the workpiece. Theworkpiece should not be mistaken for a grou
26、nd connection.Fumes and Gases. Many welding, cutting, and allied processes producefumes and gases which may be harmful to health. Avoid breathing the air inthe fume plume directly above the arc. Do not weld in a confined area with-out a ventilation system. Use point-of-welding fume removal when weld
27、-ing galvanized steel, zinc, lead, cadmium, chromium, manganese, brass, orbronze. No container should be presumed to be clean or safe. Do not weld orcut on any container, including piping, until it has been examined by,cleaned under the supervision of, and rendered safe by qualified personnel.Compre
28、ssed Gas Cylinders. Keep caps on cylinders when not in use.Make sure that gas cylinders are chained to a wall or other structural sup-port. Do not weld on cylinders.Radiation. Arc welding may produce ultraviolet, infrared, or light radia-tion. Always wear protective clothing and eye protection to pr
29、otect the skinand eyes from radiation. Shield others from light radiation from your weld-ing operation.AWS recommends a personal copy of Arc Welding Safely, Fire Safety in Welding and Cutting, Recommended Safe Practices for the Preparation for Welding andCutting of Containers and Piping, and Safety
30、in Welding, Cutting, and Allied Processes.viiiAg SilverAl AluminumAr ArgonB BoronBe BerylliumC CarbonCd CadmiumCo CobaltCO2Carbon DioxideCr ChromiumCu CopperFe IronHe HeliumLa LanthanumLi LithiumMg MagnesiumMn ManganeseMo MolybdenumN NitrogenNb NiobiumNi NickelO OxygenP PhosphorusS SulfurSe Selenium
31、Si SiliconSn TinTa TantalumTi TitaniumV VanadiumW TungstenZn ZincZr ZirconiumAbbreviation Quick Reference1The terms in this chapter are common words used in dealing with weld-ing of stainless steels. See the latest revision of AWS A3.0, Standard Weld-ing Terms and Definitions, for the standard terms
32、 used in the weldingindustry. Some other terms and definitions are standard metallurgical andcorrosion terms from ASM International and the National Association ofCorrosion Engineers (NACE).Air carbon arc cutting (CAC-A)A carbon arc cutting process variationthat removes molten metal with a jet of ai
33、r.AusteniteA nonmagnetic phase of steel with a face-centered cubic (FCC)structure.Austenitic stainless steelA stainless steel that contains chromium, nickel,and sometimes manganese, which produce austenite.Autogenous weldA fusion weld made without filler metal.Base metalThe metal or alloy that is we
34、lded.ButteringA surfacing variation that deposits surfacing metal on one ormore surfaces to provide metallurgically compatible weld metal for thesubsequent completion of the weld.Carbon arc cutting (CAC)An arc cutting process that uses a carbonelectrode.Carburizing flameA reducing oxyfuel gas flame
35、in which there is anexcess of fuel gas, resulting in a carbon-rich zone extending around andbeyond the cone.Cold crackA crack which develops after solidification is complete.CorrosionThe deterioration of a metal by chemical or electrochemicalreaction with its environment.Consumable insertFiller meta
36、l that is placed at the joint root beforewelding, and is intended to be completely fused into the joint root tobecome part of the weld.Crater crackA crack formed in the crater or end of a weld bead, typicallya form of a hot crack.Crevice corrosionCorrosion caused by the concentration of corrodentalo
37、ng crevices.DefectA discontinuity or discontinuities that by nature or accumulatedeffect (for example total crack length) render a part or product unable tomeet minimum applicable standards or specifications. The term desig-nates rejectability.Delayed crackA nonstandard term for cold crack caused by
38、 hydrogenembrittlement.DilutionThe change in chemical composition of a welding filler metalcaused by the admixture of the base metal or previous weld metal in theweld bead.DiscontinuityAn interruption of the typical structure of a material, suchas a lack of homogeneity in its mechanical, metallurgic
39、al, or physicalcharacteristics. A discontinuity is not necessarily a defect.Chapter 1Definitions2Duplex stainless steelA stainless steel that contains chromium plus otheralloying elements, designed to produce a duplex structure at room tem-perature of a mixture of austenite and ferrite, austenite an
40、d martensite,etc.ElectrodeA component of the electrical circuit that terminates at the arc,molten conductive slag, or base metal.Electron beam welding (EBW)A welding process that produces fusion(coalescence) with a concentrated beam, composed primarily of high-velocity electrons, impinging on the jo
41、int.FerriteA magnetic phase of steel with a body-centered cubic (BCC)structure.Ferrite number (FN)An arbitrary, standardized value designating theferrite content of an austenitic stainless steel weld metal.Ferritic stainless steelA stainless steel that contains chromium (and oftenmolybdenum), which
42、produce ferrite.Filler metalThe metal or alloy to be added in making a welded joint.Flux cored arc welding (FCAW)An arc welding process that uses an arcbetween a continuous filler metal electrode and the weld pool. The pro-cess is used with shielding gas from a flux contained within the tubularelect
43、rode, with or without additional shielding from an externally sup-plied gas.Fusion weldingAny welding process that uses fusion of the base metal tomake the weld.Fusion zoneThe area of base metal melted as determined on the crosssection of a weld.Gas metal arc welding (GMAW)An arc welding process tha
44、t uses an arcbetween a continuous filler metal electrode and the weld pool. The pro-cess is used with shielding from an externally supplied gas.Gas tungsten arc welding (GTAW)An arc welding process that uses anarc between a tungsten electrode (nonconsumable) and the weld pool.The process is used wit
45、h shielding gas.Heat-affected zone (HAZ)The portion of the base metal whose mechanicalproperties or microstructure have been altered by the heat of welding.Heliarc weldingA nonstandard term for gas tungsten arc welding.Hot crackA crack formed at temperatures near the completion ofsolidification.Hydr
46、ogen crackAnother term for cold crack.Inert gasA gas that normally does not combine chemically with materials.Intergranular corrosionCorrosion occurring along grain boundaries,with little attack on the surrounding grains.Interpass temperatureIn a multipass weld, the temperature of the weldarea betwe
47、en weld passes.Laser beam cutting (LBC)A thermal cutting process that severs metal bylocally melting or vaporizing with the heat from a laser beam.3Laser beam welding (LBW)A welding process that produces fusion(coalescence) with the heat from a laser beam impinging on the joint.MartensiteA hard, bri
48、ttle phase of steel with a body-centered tetragonal(BCT) structure.Martensitic stainless steelA stainless steel that contains chromium andcarbon, which produce martensite.MIG WeldingA nonstandard term for gas metal arc welding.Oxidizing flameAn oxyfuel gas flame in which there is an excess of oxy-ge
49、n, resulting in an oxygen-rich zone extending around and beyond thecone.Oxyfuel gas cutting (OFC)A group of oxygen cutting processes that useheat from an oxyfuel gas flame.Oxyfuel welding (OFW)A group of welding processes that producesfusion (coalescence) of workpieces by heating them with an oxyfuel gasflame.PassivationThe changing of a chemically active surface of stainless steelto a much less reactive state. Formation of a chromium-rich oxide layer,which is passive to corrosion or further oxidation.Pitting corrosionLocalized cor
