Glossary - W
A localised coalescence of metals or non-metals produced by heating the materials to the welding temperature, with or without the application of pressure and with or without the use of filler metal. A weld deposit resulting from a pass. Weld Bead Shape describes the physical profile of the weld metal. Weld decay (intercrystalline corrosion) in austenitic stainless steel is an "in-service" corrosion problem caused by the formation of chromium-carbides at HAZ grain boundaries during welding. These effectively remove the chromium locally and prevent it from forming a corrosion resistant surface barrier, leading to corrosion on the chromium-depleted sites. Weld decay is a historic problem and arose during service in certain environments (most notably breweries). It has now been virtually eliminated by use of low carbon or stabilised stainless steels, modern low heat input processes and low carbon or stabilised welding consumables. The exposed surface of a weld on the side of from which welding was done. Description of way the component to be joined is configured. Examples would be a butt or fillet joint. Follow this link for a more detailed explanation. A single progression of welding or surfacing along a joint or substrate. The result of a pass is a weld bead, layer, or spray deposit. The shape to which the edges of the weld joint are cut or machined prior to welding. Follow this link for a more detailed explanation. Weld metal in excess of the quantity required to fill a joint. The junction of the weld face and the base metal. A term describing the relative ease or difficulty with which a metal or alloy can be welded. A metal or alloy is considered to have good weldability if it can be welded without excessive difficulty, or the need for special, costly, welding procedures, and the resultant welded joints have suitable mechanical properties for the intended application. An assembly whose component parts are joined by welding. MIG wire can be supplied as a continuous coil wound onto cylindrical reels or spools of various designs and diameters. The amount of wire will vary with reel diameter and type of alloy. One form of reel/spool is manufactured entirely from wire. These are commonly described as 'wire baskets' and will hold about 15kg of steel MIG wire or 6kg of aluminium MIG wire. Baskets intended for use with stainless steel and non-ferrous metal MIG consumables have the wire covered by a plastic coating to prevent contamination of the welding wire. Some baskets require a 'reel adaptor' to be fitted to enable them to be attached to wire feed units (which are designed to take the traditional plastic reels), while others have such an adaptor built into them. Some alloy systems will harden when subjected to cold work ( mechanical work carried out at temperatures too low for recrystallization to occur). This plastic deformation causes dislocations to become entangled and the material hardens and becomes more resistant to further working. Welding Research Council constitution diagram for the estimation of weld metal ferrite from Chromium Equivalent and Nickel Equivalent. Used primarily with Duplex and Super Duplex stainless steels.
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