锻造温度对TC21钛合金锻板组织和力学性能的影响

Influence of forging temperature on structure and mechanical property for TC21 titanium plate

研究锻造温度对TC21钛合金锻板组织和力学性能的影响。试验选用3件规格为Φ300 mm×400 mm的TC21棒料,经制坯完成后进行锻造。采用相同锻造变形量,锻造温度分别为Tβ+15℃、Tβ+30℃、Tβ+45℃,进行显微组织观察和室温拉伸试验分析。试验结果表明,TC21锻板在相变点以上变形时,随着锻造温度升高,试样短横向、长横向和纵向室温抗拉强度Rm和室温屈服强度Rp0.2升高。由于锻造温度在相变点以上,所以3块锻板的低倍呈清晰晶,且随着锻造温度的升高,清晰度增加,晶粒增大。同时,3块锻板的显微组织为网篮组织,由多个平直的束状α相互相交错排列形成,随着锻造温度升高,α相排列方向一致性增强,长条α相含量增加,α相厚度和长度增加。

The influence of forging temperature on microstructure and mechanical property of TC21 alloy plate was investigated. Three TC21 alloy bars with a specification of tlb300 mm×400 mm were prepared for the forging test. The microstructure was observed and room temperature tensile test was analyzed under the forging temperatures of Tβ ＋ 15℃, Tβ ＋ 30℃ and Tβ ＋45℃ respectively based on the same forging deformation. The results show that room temperature tensile strength Rm and room temperature yield strength Rp0.2 on short transversal, long transversal and longitudinal direction increase with the rise of forging temperature when TC21 forging plate deforms above transformation temperature. Because forging temperature was above the transformation temperature, the maerocopic structure of three plates is clear grain, and grain grows clearer and larger with rising forging temperature. The microcopic structure of three plates is basketwave structure which is formed by much stagger flat beam α phase, α phase orientation grows more consistent, strip α phase is increased, and the thickness and length of α phase are increased with the rise of forging temperature