【摘要】 分析了18CrMnN iMo钢螺旋伞齿轮渗碳淬火后表面产生裂纹的原因。结果表明,齿轮渗碳时由于气氛碳势过高造成渗层组织中的碳化物沿晶界呈连续网状分布增大了渗层的脆性,而齿轮渗碳空冷后产生的表面拉应力导致裂纹沿晶界产生和扩展,因此网状碳化物是产生表面裂纹的主要原因。更多还原

【Abstract】 The cause of surface cracks generated in 18CrMnNiMo steel spiral bevel gear after carburizing and quenching was analyzed.The results show that the continuous network carbides distribute along the grain boundary will increase the brittleness of carburized layer because of the high carbon potential in atmosphere when gear is carburized.The surface tensile stress generated by cooling shrinkage of the gear after carburizing induces the initiation and expansion of crack along grain boundary.The continuous network of carbide distribute along the grain boundary is the main reason of surface crack initiation.更多还原