Al_2O_3弥散强化Cu基复合材料高温拉伸行为研究

Tensile Behavior of Al_2O_3 Dispersive Strengthened Copper-based Composite at Elevated Temperature

Al2O3颗粒弥散强化铜基复合材料因具有高强度和高导电性而在电子行业和电阻焊行业有着广阔的应用前景,本文利用扫描电子显微镜和透射电子显微镜对内氧化法制备的Al2O3/Cu复合材料的显微组织进行了分析,并用高温电子拉伸试验机测试了其高温拉伸力学性能。结果表明,Cu 0.6%Al2O3复合材料的室温拉伸屈服强度为442MPa,600℃时屈服强度为154MPa;试验温度低于300℃,其断面收缩率为22.2%～62.0%,温度高于400℃,其断面收缩率为4.5%～9.1%,呈现出明显的高温脆性。对其拉伸断口形貌和断裂机理进行了初步分析。

The Al_2O_3 particulates reinforced copper-based composites with high strength and high conductivity at ambient temperature have great potential applications in electrical industry and resistance welding industry. A novel Al_2O_3 particulates reinforced copper-based composite is fabricated by means of internal oxidation method. The microstructure of the composite is investigated under transmission electron microscope (TEM) and scanning electron microscope (SEM). The tensile strength and plasticity of the composite are determined at the temperature range of 25～1000℃. Results show that the Al_2O_3/Cu composite presents excellent high yield strength and high fracture strength at elevated temperature. The yield strength reaches 154MPa at 600℃.Brittle fracture occurs at elevated temperature with contrast to the ductile fracture at ambient temperature. The brittle fracture mechanism is discussed in brief.