(1. 陜西理工學(xué)院 材料科學(xué)與工程學(xué)院，漢中 723003；2. 陜西理工學(xué)院 圖書館，漢中 723003)
摘 要: 采用TEM和拉伸實(shí)驗(yàn)研究經(jīng)300、400和500 ℃分別時(shí)效0.5~100 h后，時(shí)效溫度和時(shí)效時(shí)間對(duì)Ti-50.8Ni-0.5V(摩爾分?jǐn)?shù)，%)形狀記憶合金室溫顯微組織和超彈性(SE)的影響。結(jié)果表明，時(shí)效溫度對(duì)合金析出相形貌和SE特性的影響比時(shí)效時(shí)間顯著。隨時(shí)效溫度的升高，合金中Ti3Ni4析出物形態(tài)由顆粒狀向針狀再向粗片狀演變，合金的應(yīng)力誘發(fā)馬氏體相變臨界應(yīng)力(σM)降低，SE特性變差。300 ℃時(shí)效態(tài)合金的σM最大，SE最好；500 ℃時(shí)效態(tài)合金的σM最小，SE最差。隨時(shí)效時(shí)間的延長(zhǎng)，300 ℃時(shí)效態(tài)合金的SE特性穩(wěn)定，σM和超彈性能耗降低；400和500 ℃時(shí)效態(tài)合金的超彈性殘余應(yīng)變?cè)黾樱琒E特性逐漸消失。
關(guān)鍵字: Ti-Ni-V合金；形狀記憶合金；時(shí)效；顯微組織；超彈性
（1. School of Materials Science and Engineering, Shaanxi University of Technology, Hanzhong 723003, China;2. Library, Shaanxi University of Technology, Hanzhong 723003, China）
Abstract:The effects of aging temperature and aging time on the microstructure and superelasticity (SE) at room temperature of Ti-50.8Ni-0.5V (mole fraction, %) shape memory alloy aged at 300, 400 and 500 ℃ for 0.5-100 h, respectively, were investigated by TEM and tensile test. The results show that the effects of aging temperature on the precipitate morphology and SE property are more outstanding than those of aging time. With increasing aging temperature, the morphology of Ti3Ni4 precipitates in the alloy changes from the fine particle-shape to the needle-shape and then to the plate-shape; the critical stress for inducing martensitic transformation (σM) decreases; and the SE property becomes poor. The σM is the largest and the SE property is the best for the alloy aged at 300 ℃, and the σM is the smallest and the SE property is the worst for the alloy aged at 500 ℃. With increasing aging time, the SE property is stable, the σM and the superelasticity energy dissipation decrease for the alloy aged at 300 ℃; the residual strain of the superelasticity increases and SE property disappears gradually for the alloy aged at 400 and 500 ℃.
Key words: Ti-Ni-V alloy; shape memory alloy; aging; microstructure; superelasticity
