Heating of Forging Billets Using the Pulsed Homopolar Generator

摘要

Research was undertaken to: (1) determine the repeatability of peak temperature of successive identical billets; (2) heat billets having widely differing resistivities; (3) observe the effect of variation in clamping force; (4) explore the range of obtainable billet heating and cooling rates; (5) study the effects of billet aspect (L/D) ratio; and (6) estimate the cost of heating billets using the homopolar billet heating process. Cylindrical billets of AISI-SAE 1022 and 1043 ferritic steels, Type 304 austenitic stainless steel, and Type 6061 aluminum were heated to their forging temperatures within 2 to 4 seconds. Scale loss with the ferritic steels was less than 0.5 percent and heating of billets was uniform over their cross sections. The process is shown to be attractive for heating non-magnetic billets or materials with high resistivities, but is said to be more expensive than induction heating if used to heat ferritic steel billets.