回火温度对超高强度35Cr3Ni2SiMnMoVA钢组织与性能的影响

Effect of tempering temperature on microstructure and mechanical properties of ultra high strength 35Cr3Ni2SiMnMoVA steel

通过力学试验、SEM、TEM等方法研究了新型低合金超高强度35Cr3MnSiNi2MoVA钢回火后的组织和力学性能。结果表明,与D6AC钢相比,35Cr3MnSiNi2MoVA钢的抗拉强度提高了400MPa以上,同时具有良好的断裂韧性;其淬火组织为板条马氏体+残留奥氏体,回火过程中析出ε-碳化物,并有良好的回火稳定性,最佳回火温度区间为280~320℃。

Effect of tempering temperature on mechanical properties and microstructure of a new low alloyed ultra high strength35Cr3MnSiNi2MoVA steel was investigated by using mechanical test,transmission electron microscope（ TEM） and scanning electron microscope（ SEM）. The results show that 35Cr3MnSiNi2MoVA steel has good properties. Compared with D6 AC steel,the tensile strength of the tested steel is improved 400 MPa or more,as well as good fracture toughness; the microstructure of 35Cr3MnSiNi2MoVA steel after hardening is martensite ＋ retained austenite,ε-carbide is precipitated in martensite laths during tempering; the tested steel has good tempering stability,its best tempering temperature interval is 280-320 ℃.