INDUCTION HARDENING METHOD FOR ALLOYED CAST IRON

摘要

PURPOSE:To obtain desired surface hardness and hardness penetration without causing quench crack by subjecting the desired part of a product to high-frequency heating and then by carrying out cooling by air injection. CONSTITUTION:A high-frequency electric current is sent to a coil 3 while revolving a camshaft 1 so as to heat e.g. a journal part 2 of the camshaft. If the desired hardness penetration is about 0.5-3mm, the surface temp. is held at 930-950 deg.C for about 10-15sec. Directly after the conclusion of heating, air is jetted from a jet orifice 5 to carry out cooling.