【摘要】 对比研究了未添加和添加钒的CrNiMo系锻钢在25,400,600,800℃的拉伸性能和拉伸后的显微组织演变,分析了钒对试验钢超塑性的影响。结果表明:随着试验温度的升高,两种试验钢的强度下降、塑性增大,未添加钒的试验钢在800℃的伸长率为71%,添加钒后达到154%,表现出超塑性;未添加钒的试验钢的显微组织为均匀的板条状马氏体,添加钒后的为马氏体+残余奥氏体+碳化钒,碳化钒起到细晶强化和析出强化作用;高温软化作用削弱了碳化钒的强化作用,但增强了其塑韧化作用。更多还原

【Abstract】 The tensile properties at 25,400,600,800 ℃ and tensiled microstructure evolution of CrNiMo series forged steel with and without vanadium were studied and compared.The effect of vanadium on the superplasticity of the tested steels was analyzed.The results show that with the test temperature rising,the strength decreased and the plasticity increased of the two tested steels.The elongation at 800 ℃ of the tested steel without vanadium was 71%,while that after the addition of vanadium reached 154%,indicating a superplasticity.The microstructure of the tested steel without vanadium was homogeneous lath martensite,while that with vanadium was mainly martensite+retained austenite+vanadium carbide.Vanadium carbide provided fine grain strengthening and precipitation strengthening.High temperature softening weakened the strengthening effect of vanadium carbide but enhanced its plasticizing effect.更多还原