粉末冶金Ni56Fe19Al25合金的相态与超弹性行为

Phase States and Super-Elasticity Behavior of Powder Metallurgical Ni56Fe19Al25 Alloy

摘要:

用粉末冶金技术制备Ni56Fe19Al25合金，将Ni、Fe、Al的元素粉与预合金粉等量混合后在500 MPa下压制成形，于1280 ℃温度烧结后进行热处理，对合金烧结态和淬火态进行X射线衍射(XRD)分析及力学性能检测。结果表明：粉末冶金技术制备的Ni56Fe19Al25合金烧结态为(β+γ)双相组织，淬火态处于(β′+γ)双相区。Ni56Fe19Al25合金淬火态在应力作用下呈现出良好的线性超弹性，抗拉强度达850 MPa，最高弹性变形量大于4.5%，断裂前总变形量达到9.2%。

Abstract:

Ni56Fe19Al25 alloys were prepared by powder metallurgy from mixing elementary and pre-alloyed Ni, Fe and Al powder. The alloys were sintered at 1280 oC after shaping under 500 MPa, and then quenched in water. The sintered and quenched alloys were studied by X-ray diffraction (XRD) and tensile strength measurement. The results show that the as-sintered Ni56Fe19Al25 alloy is of (β+γ) dual-phase, and the as-quenched alloy is of (β′+γ) dual-phase. The as-quenched Ni-Fe-Al alloy under stress presents good linear super-elasticity; the tensile strength is 850 MPa, the total deformation amount before fracture reaches to 9.2%, and the largest elastic deformation is over 4.5%.