The Effect of Chemical Composition,Microstructure on the Mechanical Properties of Wheel Steels

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.