Ti-6321钛合金棒材热变形及热处理工艺研究

Study of Heat Deformation and Heat Treatment Process of Ti-6321 alloy bars

摘要:

对Ti-6321钛合金棒坯在两相区进行加热，再经过50%~80%的精锻热变形和普通退火后，发现原始棒坯的组织类型并没有发生改变，但α相组织的拉长特征得到明显改善。随着变形量增大，晶粒细化程度逐步提高，棒材强度呈上升趋势，冲击韧性呈下降趋势。对Φ45mm规格棒材进行了普通退火、双重退火、β退火和固溶时效热处理实验，结果表明，Ti-6321合金棒材的组织和性能对热处理工艺较为敏感，应根据使用环境的具体要求，选择适宜的热处理工艺，最终实现材料强度、塑性和韧性的良好匹配。

关键词:Ti-6321钛合金;变形量;热处理;显微组织;性能

Abstract:

Ti-6321 titanium alloy billets have been heated in (α β) phase region and forged at the deformation range of 50%~80% and undergone conventional annealing, we can find that the microtructure types of original billets have not been changed, but the elongated α phase structure have been crushed obviously.With the increasing of deformation, the degree of grain refinement is improved gradually, the strength of bars increased and the impact toughness of bars decreased. The bars with 45 mm diameter have been heat treated by conventional annealing, dual annealing, β annealing, and solution annealing and aging, the result shows that the microstructure and properties of Ti-6321 alloy bars are sensitive to heat treatment process and the optimum heat treatment method should be chosen to achieve a appropriate combination of strength, plasticity and toughness according to the special requirements.

Key words:Ti-6321 titanium alloy; deformation; heat treatment; microstructure; property