Procedures for HSS Welding

About High Speed Steel

• HSS is used to make a variety of tools used in manufacturing processes, such as drill bits, power saw blades, mills and turning tools for the metalworking industry. A few tools used for woodworking are also made of high speed steel. HSS has a number of designations, including M1, M2, M7 and M50. Each of these may be used for different tasks, balancing the hardness and brittleness of the steel for the most effective results. For instance, M1 is the hardest of high speed steels, but it is also the most brittle and is not used when breakage frequently occurs. The amount of alloy in these high speed tool speeds may be up to 25 percent of the composition of the material.

Welding High Speed Steel

• High speed steels are welded by a number of methods including spot welding, MIG welding or TIG welding. MIG welding, or metal inert gas, welding uses gases to shield the work area being welded from contaminants in the air. TIG welding uses tungsten as a shielding gas and is used to create a more refined appearance on the metal part. HSS may require special techniques for successful repair and joining of the material.

HSS Welding Procedures

• The proper electrode for the high speed steel is selected by determining the composition of the material. This determination may require contacting the manufacturer to learn the exact components in the material. The part is first ground or machined and all contaminants removed from the surface. High speed steels require pre-heating to properly disperse the heat from welding over a wider surface of the material. Use an oxyacetylene torch to pre-heat the surface. Then, apply the minimum arc voltage and amperage to create a straight edge slowly along the surface, moving the electrode away from the edges and corners. The material should be wire-brushed and deslagged, that is, the small particle of the molten metal removed in-between the passes of welding. Peen, or lightly hit with a hammer, each bead after it has been deposited.

Post-Welding Procedures on HSS

• HHS welding requires careful post-heating to minimize the occurrence of cracking of materials. Cool the weld slowly, then re-heat and cool once again. This process refines the grain surface and minimizes internal welding stresses.