(南昌航空大學 航空制造工程學院 輕合金加工科學與技術(shù)國防重點學科實驗室，南昌 330063)
摘 要: 對TA15合金在拉伸試驗機上進行應變速率敏感因子( 值)高效超塑性變形試驗，研究合金的超塑性性能和顯微組織。結(jié)果表明：在780~950℃變形時，TA15合金呈現(xiàn)出良好的超塑性能；900 ℃變形時，該合金的超塑性能最好， 值達到0.62，最大伸長率為1287%；隨著變形溫度的升高，合金的超塑性能降低，950 ℃時伸長率僅為567%。顯微組織分析表明：TA15合金在超塑性變形過程中，晶粒始終保持等軸狀；由于變形溫度升高，晶粒合并長大，950 ℃時發(fā)生 → 相轉(zhuǎn)變，初生 相體積分數(shù)大幅度降低。與最大 值法相比較， 值高效超塑性變形不僅使TA15合金獲得了良好超塑性能，變形效率也顯著提高。
關(guān)鍵字: TA15合金；超塑性； 值；顯微組織
（National Defence Key Discipline Laboratory of Light Alloy Processing Science and Technology,
School of Aeronautical Manufacturing Engineering, Nanchang Hangkong University, Nanchang 330063, China）
Abstract:The high efficient superplastic deformation experiments of TA15 alloy based on m value were performed on the tensile testing machine. The superplastic properties and microstructure were studied. The results indicate that TA15 alloy exhibits excellent superplasticity at temperatures of 780-950 ℃. The superplasticity is the best at 900 ℃. The m value is 0.62 and the maximum elongation is 1287%. With temperature increases, the superplasticity decreases and the elongation is only 567% at 950 ℃. The microstructure analysis shows that the equiaxed grains are kept during deformation. The grains merge and grow up due to increasing temperature. The volume fraction of primary phase decreases greatly because → phase transformation occurs at 950 ℃. Compared with the method of maximum m value, not only the excellent superplasticity of TA15 alloy is obtained by the high efficient superplastic deformation, but also the deformation efficiency is enhanced obviously.
Key words: TA15 alloy; superplasticity; m value; microstructure
