工具鋼及び合金白鋳鉄の3元アブレシブ摩耗挙動に及ぼす炭化物の影響

抄録

  Influences of carbides on three body abrasive wear behavior were investigated for carbon tool steels (SK85 and SK105), alloy tool steels (SKS3, SKD61, SKD11 and SKH51) and alloyed white cast irons (Ni-hard, 16%Cr and multi-component cast irons) by means of rubber wheel wear test using SiO₂ abrasives with 240μm in average diameter. Wear loss of the materials (SK85, SK105, SKS3 and SKD61) without crystallized carbides increased once up to the maximum hardness of 650 to 700HV30, and then, decreased. In the case of materials (SKD11, SKH51, Ni-hard, 16%Cr and multi-component cast irons) with crystallized carbides, the wear loss decreased gradually with an increase in hardness. It was clarified from the results obtained that the carbides crystallized in the materials played important roles in the behavior of the three body abrasive wear. Furthermore, in the steel materials without crystallized carbides, those containing secondary complex carbides with higher hardness and less retained austenite showed better wear resistance compared to the materials with secondary carbides with lower hardness and with some retained austenite. It was also found that the cast iron materials containing crystallized carbides such as MC, M₂C and M₇C₃ with higher hardness than M₃C carbide showed more outstanding wear resistance.