Research on the Properties of Grind-Hardening and Abrasion of 42CrMo Steel in Agricultural Diesel Engine Crankshaft

In order to improve the strength and wear-resistance of agricultural diesel engine crankshaft, the grinding-hardening experiment of crankshaft material 42CrMo steel was carried out on MM7132 surface grinder. Microstructure of the specimens was observed with SSX-550 scanning electron microscope (SEM) and the abrasion experiment was carried out on ML -100 abrasive wear testing machine. The results showed that the maximum mircrohardness of 42CrMo steel after grind hardening was 850HV and the maximum depth of grind hardening layer was 1.25mm. The hardened layer was fully occupied by lath martensite; a little of martensite and much tempered sorbite appeared in the transitional region. The wear-resistance of the specimens after grind hardening was improved by three times.