Ti/Al合金化对U-5.5Mo合金组织与力学性能的影响

Effect of Ti / Al Alloying on Microstructure and Mechanical Properties of U-5.5Mo Alloy

摘要:

采用感应熔炼法在U-5.5Mo合金中引入Ti/Al元素,通过淬火与时效热处理来调控材料的组织与性能,获得不同热处理状态下的U-Mo-Ti/Al合金的微结构与性能。并分析析出相的组成、分布与性能的关系,探讨Ti/Al合金元素对U-5.5Mo合金力学性能的调控机制。发现在U-5.5Mo合金中加入微量Ti元素对U-Mo合金有明显固溶强化效果,使合金强度大幅提升；低温时效热处理可大幅提升U-Mo-Ti三元合金的力学性能；添加微量Al元素,促使U-Mo-Ti-Al四元合金中形成高温稳定的富钛与富铝的多元复合金属间化合物,其在基体与晶界上呈大量不规则连续分布,对合金具有显著沉淀强化效果,使U-Mo-Ti-Al四元合金的强度大幅提升,而塑性几乎降为零。

Abstract:

An experimental set-up was designed for measuring the self-field losses of Bi2223/Ag HTS tapes using a transport current method. Ti/Al was introduced into U-5.5Mo alloy by induction melting, and a new alloy U-Mo-Ti/Al is obtained in this way, its microstructures and properties are controlled by quenching and heat treatment of aging. The relationship between the composition, distribution and properties of precipitates was analyzed, the effect of Ti/Al alloy elements on the mechanical properties of U-5.5Mo alloy was investigated as well. It is found that added trace element Ti has obvious effect of solution strengthening on the alloy of U-5.5Mo. The mechanical properties of U-Mo-Ti ternary alloy can be greatly improved by low temperature aging. It can promote the formation of stable multi-component intermetallic compounds rich in titanium and aluminum in U-Mo-Ti-Al quaternary alloy under high temperature by adding trace element Al, multitudes of irregular continuous distribution of the trace element in the matrix and grain boundary have significant precipitation strengthening effect on the alloy, as a result, the strengthen of U-Mo-Ti-Al quaternary alloy is greatly improved while the plasticity almost decreases to zero.