HAYNES ® 188 alloy - Haynes International, Inc.

WELDINGHAYNES 188 alloy is readi ywelded by Gas Tungsten Arc(TIG), Gas Metal Arc (MIG),Shie ded Metal Arc (coatedelectrodes), electron beamwelding and resistance weldingtechniques. Its welding characteristics are similar to those forHAYNES 25 alloy. SubmergedArc welding is not recommended as this process ischaracterized by high heatinput to the base metal andslow cooIng of the weld. Thesefactors can ncrease weldrestraint and promote cracking.Base Metal PreparationThe joint surface and adjacentarea should be thoroughlycleaned before welding. Allgrease, oil, crayon marks, sulfur compounds and otherforeign matter should beremoved. Contact with copperor copper-bearing materials inthe joint area should beavoided. It is preferable, butnot necessary, that the alloy bein the solution-annealed condition when welded.Filler Metal SelectionMatching composition fillermetal is recommended for joining 188 alloy. For joiningsection thicknesses greaterthan 3/8 in. (9.5 mm) 230~Wwfiller wire is suggested. Forshielded metal arc welding,HAYNES 25 alloy electrodes(AMS 5796) are suggested. Fordissimilar metal joining of 188alloy to nickel-, cobalt- or ironbasematerials, 188 alloy itself,230-W filler wire, 556TM alloy,HASTELLOY S alloy (AMS5838) or HASTELLOY W alloy(AMS 5786, 5787) weldingproducts are suggested,depending upon the particularcase.Preheating, InterpassTemperatures and Post-WeldHeat TreatmentPreheat is not usually requiredso ong as base meta to bewelded is above 32 F (0°C).Interpass temperatures generally should be low. Auxiliarycooling methods may be usedbetween weld passes, asneeded, prov d ng that suchmethods do not introduce contaminants. Post-weld heattreatment is not normal yrequired for 188 alloy. For further information, please contactHaynes International.HEALTH AND SAFETY INERMATIONWelding can be a safe occupation. Those in the weldingindustry, however, should beaware of the potential hazardsassociated with welding fumes,gases, radiation, electricshock, heat, eye injuries, burns,etc. Also, local, municipal,state, and federal regulations(such as those issued byOSHA) relative to weldng andcutting processes should beconsidered.Nickel-, cobalt-, and iron-basealloy products may contain, invarying concentrations, the following elemental constituents:auminum, cobalt, chromium,copper, iron, manganese,molybdenum, nickel and tungsten For specificconcentrations of these andother elements present, refer tothe Materal Safety Data Sheets(MSDS) H3095 and H1072 forthe product.Inha ation of metal dust orfumes generated from weldng,cutting, grind ng, melting, ordross handling of these alloysmay cause adverse healtheffects such as reduced lungfunction, nasal and mucousmembrane irritation. Exposureto dust or fumes which may begenerated in working withthese alloys may alsocause eye irritation, skin rashand effects on other organsystems.The operation and maintenance of welding and cuttingequipment should conform tothe provisions of AmericanNat onal Standard ANSI/AWSZ491, (Safely in Welding andCuffing”) Attention s especia y cal ed to Section 7(Protect on of Personnel) and 8(Heath Protect on andVentilat on) of ANSI/AWS Z491.Mechanical ventilation s advisable and, under certainconditions such as a very confined space, is necessaryduring welding or cuffing operations, or both, to preventpossible exposure to hazardous fumes, gases, or dustthat may occur.HAYNES 188 alloy