Ni_(50-x)Ti_(50)La_(x)形状记忆合金的力学性能

Mechanical Properties of Ni_(50-x)Ti_(50)La_(x) Shape Memory Alloys

通过掺杂稀土元素La,近等原子比NiTi形状记忆合金的微结构发生改变,进而影响合金的力学性能。通过实验方法研究了掺杂少量La元素的Ni_(50-x)Ti_(50)La_(x)(x=0.1,0.3,0.5,0.7)三元合金的力学性能,结果表明:Ni_(50-x)Ti_(50)La_(x)合金的硬度随La元素掺杂量的增加而增大,弹性模量随La元素掺杂量增加未呈现出明显的变化,屈服强度和拉伸强度在La元素掺杂量为0.3at.%时达到最大值,断裂伸长率随着La元素掺杂量的增加而减小。断口形貌分析表明:合金的断裂主要为解理断裂,并随着La元素掺杂量的增加,合金的塑性降低。

By doping element La,the microstructure of the equiatomic composition NiTi shape memory alloys were changed,to affect the mechanical properties of the alloys.The mechanical properties of Ni_(50-x)Ti_(50)La_(x)(x=0.1,0.3,0.5,0.7)alloys were investigated experimentally.The results show that the hardness of Ni_(50-x)Ti_(50)La_(x)alloys increases with increase of La fraction,and the elastic modulus does not change obviously,the yield strength and tensile strength reach a maximum when La is 0.3at.%,and the rupture elongation decreases with increase of La fraction.The fracture morphology shows that the cleavage fracture of the alloys is the main fracture,and the plasticity of the alloys decreases with the increase of La fraction.