Ti-36Nb-2Ta-3Zr-0.35O 合金在热加工与冷加工过程中的组织演变

摘要

采用元素粉末法通过冷等静压、真空烧结、热锻、冷锻等方法制备了 Ti−36Nb−2Ta−3Zr−0.35O(质量分数，%)(TNTZO)合金。运用透射电子显微镜、扫描电子显微镜、金相显微镜以及万能试验机对加工前后合金材料进行显微组织分析和力学性能检测，探究热加工与冷加工对合金组织与性能的影响。结果表明：TNTZO 合金具有良好的可加工性，通过热锻与冷旋锻可以得到良好的细晶组织；85%冷旋锻的合金样品呈现典型大理石状显微组织，并且在其冷加工过程中伴随有应力诱导α"马氏体相变。此外，热加工与冷加工后合金的强度及塑形都有显著提高。%The Ti−36Nb−2Ta−3Zr−0.35O (mass fraction, %) (TNTZO) alloy was produced by cold isostatic pressing and sintering from elemental powders, followed by hot and cold deformation. The effects of deformation process on microstructures and mechanical properties were investigated using the SEM, TEM, OM and the universal material testing machine. Results show that the alloy can be easily hot forged and cold swaged due to the fine-grained microstructure. Only after cold swaging by 85%, the alloy shows the typical “marble-like” structure. And the cold deformation is accompanied by stress-induced α" phase transformations. Moreover, both the strength and the ductility of the alloy are significantly improved by hot and cold working.