钒对含碳化物等温淬火球墨铸铁组织及性能的影响

Effects of Vanadium on Microstructures and Properties of CADI

研究了钒对含碳化物等温淬火球墨铸铁(CADI)的组织、力学性能及耐磨性能的影响。结果表明,铸态下,随着含钒量的增加,组织中碳化物的数量逐渐增多,经过900℃的奥氏体化保温1.5 h+250℃等温淬火保温1.5 h热处理后,含钒0.4%的试样组织为下贝氏体+10%碳化物+残余奥氏体。经测试含钒0.4%的试样综合性能最佳,抗拉强度为1070MPa,硬度为HRC 52.9,冲击韧度为28.26 J/cm2,磨损率为0.54 mg/m,相对耐磨性比不加钒时提高了24%。

The effects of different vanadium content on microstructure and properties of carbide austempered ductile iron （CADI） were researched. The results show that the amount of carbide in the as-cast specimens increases with the increase of vanadium content. After austenited at 900 ℃ for 1.5 h and austempered at 250 ℃ for 1.5 h, the sample containing 0.4% vanadium has the best mechanical properties. After heat treatment, the microstructure of the sample is composed of resiudal austenite, lower bainite and 10% carbide. Its tensile strength is 1 070 MPa, hardness is HRC 52.9, impact toughness is 28.26 J/cm^2 and wear rate is 0.54 mg/m, relative wear resistance is increased by 24% than that of samples without vanadium.