旋锻对Mo-Ti-Zr合金性能及显微组织的影响  

Influence of rotary forging on mechanical properties and microstructure of Mo-Ti-Zr alloy

作　　者：罗明[1] 范景莲[1] 成会朝[1] 田家敏[1] 卢明园[1] 

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2010年第1期97-102,共6页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金委员会创新研究群体科学基金资助项目(50721003);国防军工新材料项目(JPPT-115-2-662)

摘　　要：将Mo粉、Ti粉和Zr粉按质量比99.35:0.55:0.10混合,采用冷等静压和1920℃高温烧结制备直径为28mm的Mo-Ti-Zr合金棒材,然后,将合金棒材进行旋锻形变强化后续处理。研究旋锻工艺对Mo-Ti-Zr合金棒材密度、硬度等性能和组织结构变化的影响。研究结果表明:随着变形程度的增加,Mo-Ti-Zr合金棒材的相对密度和硬度逐步提高;在1250℃旋锻,当断面收缩率为33%时,Mo-Ti-Zr合金棒材相对密度提高到98.5%,洛氏硬度(HRB)为92.8。当断面收缩率为19.2%时,Mo-Ti-Zr合金棒材致密化速率最低;烧结态Mo-Ti-Zr合金棒材断口呈现典型的沿晶脆性断裂特征,晶界强度低;在1250℃旋锻,当断面收缩率达到33%时,Mo-Ti-Zr合金棒材转变为穿晶和沿晶的混合型断裂,晶界强度增加;在1380℃旋锻时,晶粒发生合并与长大。Mo-Ti-Zr alloy rods with diameter of 28 mm were prepared by mixing the elemental powders according to the mass ratio of m（Mo）：m（Ti）：m（Zr）=99.35：0.55：0.10, cold isostatic pressing and high temperature sintering at 1 920 ℃, then the alloy rods were rotary forged. The influences of the rotary forging process on the relative density, hardness and microstructure of Mo-Ti-Zr alloy rods were investigated. The results are as follows. The relative density and hardness of Mo-Ti-Zr alloy rods increase gradually with the increase of deformation amount. The relative density of Mo-Ti-Zr alloy rods reaches 98.5% and hardness （HRB） is 92.8 after rotary forging to deformation amount of 33% at 1 250 ℃. The increase of relative density of Mo-Ti-Zr alloy rods reaches the lowest after rotary forging to deformation amount of 19.2%. The fracture type of sintered Mo-Ti-Zr alloy rods is of intergranular fracture and the grain boundary strength is weak. The fracture type of Mo-Ti-Zr alloy rods changes to the mixing type of transgranular fracture and intergranular fracture and the grain boundary strength is strengthened after rotary forging to deformation amount of 33% at 1 250 ℃. The molybdenum grains mergence and growth occur after rotary forging at 1 380 ℃ .

关 键 词：Mo-Ti-Zr合金棒材 旋锻 相对密度 断口形貌 

分 类 号：TF125.2[冶金工程—粉末冶金]