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°C, TiNiNb alloy performs 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.