微量TiC/ZrC对TZM合金室温及高温性能与组织的影响

Effect of Trace TiC/ZrC on Property and Microstructure of TZM Alloy at Room and High Temperature

摘要:

采用粉末冶金方法制备Mo-Ti-Zr-TiC/ZrC合金，研究微量TiC/ZrC对合金性能与组织的影响。结果表明，添加微量TiC/ZrC后合金性能得以明显提高，TiC/ZrC添加量为0.4%（质量分数，下同）时，合金室温抗拉强度分别达到最高值。同时，微量TiC/ZrC显著提高了合金的高温强度，添加的微量碳化物粒子促进了合金高温拉伸过程中韧窝的形成，使合金高温拉伸由穿晶解理和韧窝断裂的混合断裂模式向韧窝断裂转变。

Abstract:

Mo-Ti-Zr-TiC/ZrC alloys were prepared via a powder metallurgy method. The effects of trace TiC/ZrC additive on the mechanical properties and microstructure of TiC/ZrC reinforced TZM alloy at room and high temperature were studied. The results indicate that the relative density and the tensile strength of Mo-Ti-Zr-TiC/ZrC alloy at room temperature are effectively enhanced by adding trace TiC/ZrC (0.1wt%~0.5wt%). The tensile strength achieves the highest value when the content of TiC/ZrC is 0.4wt%. Meanwhile, Mo-Ti-Zr-TiC/ZrC alloy with 0.4wt% TiC/ZrC shows excellent mechanical properties at 800 °C. The dispersive distribution of trace carbide particles accelerates the formation of dimples in the tensile procedure at elevated temperature, which leads to the transformation of fracture mechanism from the compound of trans-granular cleavage fracture and dimple fracture to simplex dimple fracture pattern.