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軸套材料：

直淬鋼(Dierct harden steel): GCrlS ( 52100)??42CrMo (4140 )??45(1045)

滲碳鋼(Carburizing steel): 20Cr ( 5120 )??20CrMo(4118)??20CrNiMo(8620H)

銅(Copper):ZCuZn24AI6Mn3Fe3??ZCuAI9Fe4Ni4Mn2

彈簧鋼(Spring steel):65Mn??50CrVA??60Si2MnA

產品特點：無潤滑槽和孔