钛合金TB2热轧棒材组织与性能的试验研究

Microstructure and Mechanical Properties of Hot Rolling Stick of Titanium Alloy TB2

研究了TB2合金热轧棒材分别在β单相区和α+β两相区温度固溶,然后经不同时效处理后,其力学性能和显微组织的变化。试验研究发现,TB2轧棒热加工状态的综合力学性能较固溶处理后优良;经710℃/30minAC固溶,然后520℃/8h时效处理的试样,综合力学性能最好;相同固溶温度并时效处理,空冷试样较水淬试样性能优良;热轧态合金显微组织主要为β组织,固溶时效后为α+β两相组织;热轧态拉伸试样断口呈韧窝状塑性断口,时效后拉伸试样断口为以脆性为主的韧脆混合断口。

The microstructure and mechanical properties of titanium alloy TB2 hot rolling stick heat-treated in the α+β phase or β phase solution temperature field and followed by ageing treatment were studied. The experiments show that the alloy′s mechanical properties in hot rolling state are better than solution treatment, and the comprehensive mechanical properties are excellent after 710 ℃/30 min AC+520 ℃/8 h heat treatment. The air cooling treated specimens properties are better than that of water quenched ones. β phase microstructure is obtained in hot rolling state and α+β bi-model microstructure is observed after solution and aging treatment. The raw hot rolling stick has plastic dimple fracture surface and aging-treated specimens have plastic and brittle mixed fracture surface but brittle is main.