行為的影響
( 1. 西安交通大學(xué)潤滑理論及軸承研究所， 西安 710049;
2. 西南交通大學(xué) 摩擦學(xué)研究所, 成都 610031)
摘 要: 考察了中溫時效處理后的Ti-50.9%Ni（摩爾分數(shù)）合金在實驗溫度為20℃， 不同應(yīng)變速率下的軸向壓縮應(yīng)力—應(yīng)變力學(xué)行為。 實驗結(jié)果表明： 隨著應(yīng)變速率的增加， 合金的應(yīng)力誘發(fā)馬氏體相變臨界應(yīng)力逐漸增加， 相變平臺逐步消失， 卸載后的殘余應(yīng)變減小， 加載—卸載變形曲線的應(yīng)力（應(yīng)變）滯后也減小； 在較高加載速率下， 合金表現(xiàn)出類線性超彈性變形行為， 可獲得高達4.5%的類線性超彈性。
關(guān)鍵字: 形狀記憶合金； 相變； 超彈性； 應(yīng)變速率； 應(yīng)力—應(yīng)變曲線
TiNi shape memory alloy under compression
ZHOU Zhong-rong2, XIE You-bai1
（ 1. Theory of Lubrication and Bearing Research Institute,Xi′an Jiaotong University,
Xi′an 710049, China;
2. Tribology Research Institute, Southwest Jiaotong University, Chengdu 610031, China）
Abstract: The mechanical behavior of aged Ti-50.9%Ni(molar fraction) alloy under axial compression dynamic load was investigated under different strain rates at 20℃. The experimental results indicate that with the strain rate increasing, the critical stress for inducing martensitic transformation rises and the plateau of phase transformation disappears, while the stress (strain) hysteresis becomes smaller and the residual strain decreases. At higher strain rate, the alloy exhibits linear-like pseudoelasticity, which is up to 4.5%.
Key words: shape memory alloy; phase transformation; pseudoelasticity; strain rate; stress—strain curve
