TiNiFeNb形状记忆合金的组织结构及相变特性

通过向TisoNiso合金中加入Fe和Nb元素,制备出一种四元Ti49Ni50-xFexNb1形状记忆合金.采用X射线衍射和背散射电子衍射的方法,测试和分析了合金的相结构及微观组织形态,采用电阻法系统研究了合金的相变特性.结果表明:Nb元素的加入并没有改变TiNiFe合金的B2结构,仅导致了广极少量的富Nb相在基体中析...

Microstructure and Transformation Behavior of TiNiFeNb Shape Memory Alloys

A series of quaternary shape memory alloys Ti₄₉Ni_50-XFe_XNb₁ (at%) are prepared by adding elements Fe and Nb into alloys Ti₅₀Ni₅₀. The microstructure morphology and phase transition behavior of these alloys are studied systematically by X-ray diffraction, backscattered electron and electrical resistance measurements. It is shown that the addition of Nb does not change the phase structure of alloy TiNiFe (B2) and it just causes a tiny quantity of Nb-rich phase to precipitate in the matrix. However, the Nb addition inhibits the appearance of the R-phase in the process of phase transformation. With the increase of Fe content from 1 at% to 3 at%, the martensitic transformation temperature decreases rapidly from 273.7 K to 137.2 K. In addition,shape memory alloys Ti₄₉Ni₄₇Fe₃Nb₁ exhibites good shape memory effect and its strain recovery rate reaches 92.66% after a pre-strain of 8%.