固溶和时效处理对铝热法制备Cu-Ti合金组织和性能的影响

Cu-Ti合金作为导电弹簧，互联接插件等重要元器件的制备材料，其大规模工业制备方法和热处理工艺仍是当前铜合金领域亟需开发和推进的重点。本文采用具有工艺简单、环保节能、成本低廉等优点的铝热法制备了Ti含量分别为1.0 wt.%、4.5 wt.%、10.0 wt.%，即成分区间较大的Cu-Ti合金，且进一步采用固溶和时效处理来调控合金的综合性能。结果表明时效态的Cu-1.0 wt.%Ti和Cu-4.5 wt.%Ti合金中Ti元素主要呈固溶状态，只有非常少量尺寸较小的析出相，而Cu-10.0 wt.%Ti合金中存在大量尺寸较大的Cu4Ti相析出。随着Ti含量的增加，合金的导电率有明显降低的趋势，而硬度和强度则呈现与之相反的趋势。对于成分相同的合金，相较于固溶状态，时效后导电率先略微下降然后上升，450 °C时效4 h后，三个成分合金的导电率均高于固溶态合金；450 °C时效2 h后，Cu-1.0 wt.%Ti和Cu-4.5 wt.%Ti合金均获得了硬度、强度和延伸率的最大值，Cu-10.0 wt.%Ti合金的硬度和延伸率也获得了极大值，其屈服强度和抗拉强度则是随着时效时间呈略微下降的趋势。

Effect of solid solution and aging treatment on microstructure and properties of Cu-Ti alloys prepared by aluminothermic reaction

As a preparation material for important components such as conductive springs and interconnect connectors, the large-scale industrial preparation method and heat treatment process of Cu-Ti alloy are still the key areas that urgently need to be developed and promoted in the current copper alloy field. In the present paper, Cu-Ti alloys with Ti content of 1.0 wt.%, 4.5 wt.% and 10.0 wt.% were prepared by aluminothermic reaction, which has the advantages of simple process, environmental protection, energy saving and low cost, and the comprehensive properties of the alloys were further regulated by solution and aging treatment. The results show that the Ti elements in the aged Cu-1.0 wt.%Ti and Cu-4.5 wt.%Ti alloys are mainly in the state of solid solution with only a small amount of smaller precipitates, while there are a large amount of precipitates in the aged Cu-10.0wt.%Ti alloys. With the increase of Ti content, the electrical conductivity of the alloys shows a significant decrease trend, while the hardness and strength show the opposite trend. For the alloys with the same composition, compared to the solid solution state, the conductivity first slightly decreases and then increases with aging time. After aging at 450 °C for 4 h, the conductivity of all three component alloys is higher than that of the solid solution state alloys. After aging at 450 °C for 2 h, the hardness, strength and elongation of Cu-1.0 wt.%Ti and Cu-4.5 wt.%Ti alloys obtain the maximum values, and the hardness and elongation of Cu-10.0 wt.%Ti alloys also obtain the maximum values. The yield and tensile strength of Cu-10.0 wt.%Ti alloys shows a slightly decreasing trend with aging time.