A New Approach to Heat Treatment of High-Strength Powder Steels

Wear (pin-on-disk) tests of low-alloy powder steels (with 0.5 and 0.65% C) are performed after vacuum sintering combined with hardening. The studied alloying systems are 0.65% C + 1.5% Cr + 0.2% Mo, 0.65% C + 0.9% Ni + 0.9% Mo + 0.2% Mn and 0.5% C + 4% Ni + 1.5% Cu + 0.5% Mo. The wear resistance of the steels after the hardening sintering is an order of magnitude higher than after the conventional sintering. The wear resistance of the steels increases in the following order: pearlitic, pearlitic-bainitic, and martensitic structures. Accordingly, the hardness grows from 98 to 105 HRB.