NiTiCu合金相变过程的研究

EFFECT OF Cu ON THE MARTENSITIC TRANSFORMATION BEHAVIORS IN Ni-Ti ALLOYS

本文用差示扫描量热法研究了 Cu 对 NiTi 记忆合金马氏体相变点及相变潜热的影响。结果表明,以 Cu 代替 Ni 至30 at.%,合金仍具有良好的记忆性能;合金相变温度及相变潜热值略有变化,相变滞后明显减小;Cu 含量对合金相变类型没有影响。相变潜热值△H 与 T_0=1/2(A_s+M_s)并不存在严格的直线关系。Cu 含量超过7.5at.—%时,合金的热加工性能变差。

The effect of Cu on the transformation temperature and latent heat of trans-formation in NiTi shape memory alloys has been studied by means of DSC.It is shown thatthese alloys exhibit excellent shape memory properties.The transformation temperatureand latent heat of transformation slightly changed with increasing Cu content up to30at.-% and the thermal hysteresis obviously decreased.As the temperature is lowered,these alloys all undergo the same transformation.An exact linear relation betweenΔH and T_0= (A_s+M_s)/2 was not found.The heat workbility got worse while the Cu con-tents were more than 7.5 at.-%.