FABRICATION CHARACTERISTICSEffect of Cold Reduction and Annealing Upon Grain Size% ASTMCold Subsequent % Grain SizeReduction Anneal Recrystallization Range0 None N/A 3 1/2 - 4*10
WELDINGHAYNES ® <strong>25</strong> <strong>alloy</strong> is readilywelded by Gas Tungsten Arc(GTAW), Gas Metal Arc(GMAW), Shielded Metal Arc(coated electrodes), electronbeam welding and resistancewelding techniques. Its weldingcharacteristics are similar tothose for HAYNES 188 <strong>alloy</strong>.Submerged Arc welding is notrecommended as this processis characterized by high heatinput to the base metal andslow cooling of the weld.These factors can increaseweld restraint and promotecracking.Base Metal PreparationThe joint surface and adjacentarea should be thoroughlycleaned before welding. Allgrease, oil, crayon marks,sulfur compounds and otherforeign matter should be removed.Contact with copper orcopper-bearing materials in thejoint area should be avoided. Itis preferable, but not necessary,that the <strong>alloy</strong> be in the solutionannealedcondition whenwelded.Filler Metal SelectionMatching composition filler metalis recommended for joining <strong>25</strong><strong>alloy</strong>. For shielded metal arcwelding, HAYNES <strong>25</strong> <strong>alloy</strong>electrodes (AMS 5797) areavailable. For dissimilar metaljoining of <strong>25</strong> <strong>alloy</strong> to nickel-,cobalt- or iron-base materials, <strong>25</strong><strong>alloy</strong> itself, 230-W filler wire,556 ® <strong>alloy</strong>, HASTELLOY S <strong>alloy</strong>(AMS 5838) or HASTELLOY W<strong>alloy</strong> (AMS 5786, 5787)welding products are suggested,depending upon theparticular case.Preheating, InterpassTemperatures and Post-Weld Heat TreatmentPreheat is not usually requiredso long as base metal to bewelded is above 32°F (0°C).Interpass temperaturesgenerally should be low.Auxiliary cooling methods maybe used between weld passes,as needed, providing that suchmethods do not introducecontaminants. Post-weld heattreatment is not normallyrequired for <strong>25</strong> <strong>alloy</strong>. Forfurther information, pleasecontact <strong>Haynes</strong> <strong>International</strong>.HEALTH & SAFETY INFORMATIONWelding can be a safe occupation.Those in the weldingindustry, however, should beaware of the potential hazardsassociated with welding fumes,gases, radiation, electric shock,heat, eye injuries, burns, etc.Also, local, municipal, state,and federal regulations (suchas those issued by OSHA)relative to welding and cuttingprocesses should be considered.Nickel-, cobalt-, and iron-base<strong>alloy</strong> products may contain, invarying concentrations, thefollowing elemental constituents:aluminum, cobalt,chromium, copper, iron,manganese,molybdenum, nickel andtungsten. For specific concentrationsof these and otherelements present, refer to theMaterial Safety Data Sheets(MSDS) H3095 and H1072 forthe product.Inhalation of metal dust orfumes generated from welding,cutting, grinding, melting, ordross handling of these <strong>alloy</strong>smay cause adverse healtheffects such as reduced lungfunction, nasal and mucousmembrane irritation. Exposureto dust or fumes which may begenerated in working with these<strong>alloy</strong>s may also cause eyeirritation, skin rash and effectson other organ systems.The operation and maintenanceof welding and cuttingequipment should conform tothe provisions of AmericanNational Standard ANSI/AWSZ49.1, (Safely in Welding andCutting). Attention is especiallycalled to Section 7(Protection of Personnel) and8 (Health Protection andVentilation) of ANSI/AWSZ49.1. Mechanical ventilationis advisable and, under certainconditions such as a veryconfined space, is necessaryduring welding or cuttingoperations, or both, to preventpossible exposure to hazardousfumes, gases, or dust thatmay occur.17HAYNES ® <strong>25</strong> <strong>alloy</strong>