对国内外5种车轮钢的微观组织、准静态力学性能和疲劳性能进行测试,分析车轮钢的化学成分和微观组织对其准静态力学性能和疲劳性能的影响.结果表明:提高Mn与C元素含量之比以及Ni,Cr和Mo元素总含量,均能明显增加珠光体的弥散度,减小珠光体层片间距；细化奥氏体晶粒尺寸和增加珠光体弥散度,车轮钢的强度、塑性和韧性均有所改善；提高Mn与C元素含量之比有利于改善车轮钢的韧性特别是冲击韧度；车轮钢的疲劳裂纹萌生寿命随着奥氏体晶粒尺寸和珠光体团尺寸的细化而增加；车轮钢试样的化学成分和显微组织对疲劳裂纹扩展速率和疲劳裂纹门槛值的影响很小.%The microstructure, quasi-static mechanical properties and fatigue properties of five kinds of wheel steels home and abroad were investigated. The combination effects of chemical composition and microstructure on the quasi-static mechanical properties and fatigue properties were analyzed. It is found that increasing Mn/C ratio and the total content of Ni+Cr+Mo can increase the dispersity of pearlite and decrease pearlite interlamellar spacing. Both refining austenite grain and increase the dispersity of pearlite can improve the strength, ductility and fracture toughness of wheel steels. Higher Mn/C ratio can improve the fracture toughness and impact strength, especially the impact strength of wheel steels. The fatigue crack initiation life increases with refining the prior austenite grain and pearlite colony size. But the chemical composition and microstructure parameters have little effect on the fatigue thresholds and fatigue crack growth resistance of wheel steels.
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