REVIEW OF WELD REPAIR PROCEDURES FOR TOOL STEEL DIES USED FOR ALUMINIUM HIGH PRESSURE DIE CASTING

摘要

Weld repairs and modifications on hot work tool steel dies, inserts, and cores used for aluminium high pressure die casting (HPDC) are commonly carried out and the procedures vary greatly within the industry in Australia. Adopting the correct weld procedure, and understanding the choice of weld material used has a great bearing on the performance of the welded dies in production. This paper studies the current weld procedures conducted in-house at two large HPDC plants and in a specialist weld company used to outsource weld repairs and modifications in Australia. Weld hardness profiles on six different weld materials and two types of tool steel were compared before and after heat treatment. The chemical composition of the weld rod material and weld microstructure are also examined and discussed.