TiNiFe形状记忆合金高温应力松弛稳定性

对形状记忆合金管接头来讲,应力松弛对在服役条件下的管接头影响更大,因此,系统地研究航空用形状记忆合金管接头在服役条件下的应力松弛的稳定性具有重要的现实意义.研究了TiNiFe和TiNiNb两种管接头用形状记忆合金在不同温度条件下的应力松弛稳定性.试验在美国880型100KN-MTS实验机上进行,通过试验得到2种合金的应力松弛曲线,结果表明,TiNiFe和TiNiNb形状记忆合金在高温下,都具有很好的稳定性.TiNiNb形状记忆合金在300℃时的应力松弛稳定性稍好于TiNiFe形状记忆合金.但是,TiNiFe形状记忆合金所承受的载荷比TiNiNb形状记忆合金要高.温度对形状记忆合金高温稳定性存在很大的影响,但其对应力松弛不同阶段的影响程度不同. 

High-temperature relaxation of TiNiFe shape memory alloy

For the shape memory alloy pipe connector, the stress relaxation’s stability has more influence on the pipe connector in the working environment. So the particular study on the stress relaxation’s stability of the aero shape memory alloy pipe connectors in the working environment has vital practical significance. The stress relaxation and stability of TiNiFe and TiNiNb shape memory alloys were investigated under different temperature. The examination was experimentalized on American 880 type 100KN-MTS, through which stress relaxation curves of the TiNiNb and TiNiFe shape memory alloys were gained. It is indicated that at high temperature both alloys are of good stability. At 300℃, TiNiNb alloy performed a better stability to resist the stress relaxation than TiNiFe alloy; but TiNiFe alloy can endure higher load than TiNiNb alloy. Temperature has great influence on the high-temperature stability of shape memory alloy, but the degree of influence on the different stages of the stress relaxation is different.