论文部分内容阅读
对65Cr5Mo3W2VSiTi(LM2)钢常规淬火组织和部分等温淬火组织的冲击韧性和断裂韧性进行了测试,对比研究了显微组织(主要指 B_l和 A_R 数量)和回火温度对LM2钢下贝氏体/马氏体(B_l/M)复相组织韧性的影响。用连续扫描拉伸技术分析了裂纹的萌生、扩展至断裂全过程与显微组织的关系。通过 U 型缺口试样的示波单冲试验,分析了显微组织对裂纹萌生功和扩展功的影响及其对缺口冲击韧性的贡献。试验结果表明,含有40%～60%B_1的复相组织随后200℃回火,对钢有显著地韧化效果。文中还较详细地探讨了高碳高合金钢中复相组织的断裂机制。
The impact toughness and fracture toughness of 65Cr5Mo3W2VSiTi (LM2) steel were studied. The effects of microstructure (mainly B_l and A_R) and tempering temperature on the bainite / Effect of martensite (B_l / M) complex phase toughness. Using continuous scanning and stretching technology to analyze the crack initiation, extending to the whole process of fracture and the relationship between microstructure. The effect of microstructure on the crack initiation work and extension work and its contribution to notched impact toughness were analyzed by single-shot oscillographic test of U-notch specimens. The experimental results show that the complex phase containing 40% -60% B_1 is subsequently tempered at 200 ℃, which has significant toughening effect on the steel. The paper also discusses in more detail the fracture mechanism of complex phase in high carbon high alloy steel.