Ti-50.8%Ni合金不同温度下的力学行为

Mechanical Properties of Ti-50.8%Ni Alloy at Different Temperature

研究Ti-50.8%N i形状记忆合金丝在-50℃-110℃的力学性能以及力学性能、残余应变、屈服平台与温度之间的关系。结果表明,在不同温度下,材料表现出不同的力学特征,10℃以上材料表现出超弹性,但当温度达到110℃以上时,超弹性消失。10℃以下,材料表现出形状记忆效应。10℃左右时,应力诱发马氏体达到最大量,最大可回复应变为7.5%,此时屈服平台最宽,残余应变最小,超弹性最好。随着温度和应力的增加,不可逆塑性变形的比值增加,超弹性变形逐渐减弱以至消失。

The mechanical properties of Ti-50.8%Ni shape memory alloy wire are investigated at different temperature from-50℃ to 110℃.The relationship of mechanical properties,residual-strain and yield-platform with temperature is described.The results show that at different temperature the material performs different mechanical characteristics,the material above 10℃ performs super-elasticity,but when the temperature reaches 110℃,the super-elasticity disappears.Below 10℃ the material shows shape memory effect.The experimental results also show that when it is about 10℃ , the stress induces martensite which achieves the most massive, the maximum back strain is 7.5% , the yield-platform is the widest and the super-elasticity is the best. With the increase of both stress and temperature, the ratio of the irreversible plastic deformation in the total deformation is gradually increased. While the ratio of the reversible super-elastic deformation decreases and finally disappears.