STEEL EXCELLENT IN COLD WORKABILITY AND CARBURIZATION-HARDENING PROPERTY AND CARBURIZATION-HARDENING METHOD

摘要

PURPOSE: To provide steel excellent in cold workability and carburization- hardening properties, and suppressing the abnormal growth of ferritic crystalline grains and preventing the deterioration in its toughness. ;CONSTITUTION: This steel contains 0.15 to 0.40% C,≤1.00% Si, ≤0.40% Mn, ≤0.02% sol. Al, ≤0.006% N and 0.005 to 0.050% B, and the balance Fe with inevitable impurities and has a structure essentially consisting of an ferritic phase and a graphite phase. The steel is subjected to cold working and is thereafter subjected to carburization-hardening at 850 to 920°C. This steel is easily cold-worked to form its shape into the complicated one of automotive parts or the like, and carburization-hardening can be executed without the deterioration in its toughness.;COPYRIGHT: (C)1994,JPO&Japio