TiNi合金约束相变行为研究

研究了预变形TiNi合金应变约束态下的相变行为结果表明：7％应变TiNi合金变形后第1次应变约束相变产生的恢复应力最大，逆相变开始温度．As′最高随着约束相变循环次数的增加，合金中引入大量塑性变形，降低了TiNi合金的恢复应变，进而造成TiNi合金约束相变恢复应力最大值逐渐降低，但约束逆相变开始温度．As′从第2次相变循环开始，几乎恢复到合金变形前的原始值，且不随相变循环次数增加而改变。

Study on Constraint Transformation Behavior of Tini Alloy

The constraint transformation behavior of 7% strained TiNi alloy was investigated, and the experimental results show that the recovery stress formed at the first constraint transformation thermal cycling is the highest, and then decreases with increasing the constraint transformation thermal cycling number. It is indicated that the recovery strain of deformed TiNi alloy is decreased with increasing the constraint transformation thermal cycling number by forming the internal plastic deformation, which results in the decrease of the recovery stress. The reverse transformation start temperature As' of the deformed TiNi alloy at the first constraint transformation thermal cycling is elevated to a higher temperature, but it nearly returns to the original value of undeformed one at subsequent constraint transformation thermal cycling, and does not change with increasing the constraint transformation thermal cycling number.