Research on Hardness Matching Between 8620H Steel and 55SiMoV Steel Rubbing-pairs
Considering the non wear-resistance of rock bits's rubbing-pairs made of a claw big runway and roller,8620H and 55SiMoV steel were designed with different carbon content and surface hardness on carburizing surface. The hardness matching and surface carbon content index were optimized by orthogonal experiment and abrasion test. Experimental results give a hardness matching with highest wear resistance,that is,the surface carbon concentration and tempering hardness of 8620H steel is 1.05% and 58～59 HRC,respectively,while those of 55SiMoV steel is 0.88% and 59～60 HRC,respectively. Furthermore,the wear form of 8620H steel and 55SiMoV is superficial layer fatigue wear.