热变形加工对WC_p/2024Al复合材料组织结构和力学性能的影响

Effect of thermal deformation on microstructure and mechanical properties of the WC_p/2024Al composites

本文采用真空热压方法制备了WCp/2024Al复合材料,研究了真空热压-热锻压-热轧制等热变形加工工艺对复合材料微观组织结构和力学性能的影响.结果表明,热锻压和热轧制加工显著细化了基体Al合金组织,改善了WC颗粒的分散性,促进了两相界面的冶金结合,材料强度得到大幅度提高;高变形速率的热锻压和热轧制工艺可降低复合材料界面WAl12中间相的生成温度,大量中间相的生成导致材料塑性下降.

The WCp/2024Al composites were fabricated by a vacuum hot-pressing method.The effect of thermal deformation processes such as hot-pressing,hot-forging and hot-rolling on microstructure and mechanical properties of the composites was investigated.The results show that hot-forging and hot-rolling can refine microstructure of the Al alloy,increase homogeneity of WC particle dispersion,and improve interfacial bonding between the Al alloy and the WC particles,leading to a significant increase in tensile strength of the WC/2024Al composites.Hot-forging and hot-rolling under high deformation rates result in the formation of large amount of WAl12 intermediate phase due to the lowering of formation temperature of the intermediate phase by deformation,and as consequence,plasticity of the composites reduces.