喷射沉积制备Al-Zn-Mg-Cu合金大型坯组织性能的研究

Researches of Microstructures and Properties of Spray-Formed Al-Zn-Mg-Cu Alloy

利用Ospray公司的喷射沉积设备制备了A l11.3Zn2.4Mg1.1Cu合金,合金挤压成棒材后,经过固溶和时效处理,用万能材料实验机对其进行了力学性能测试,合金的抗拉强度为849 MPa、屈服强度为796 MPa,延伸率为3.3%。透射电镜和扫描电镜对拉伸试样微观组织的研究结果表明,合金微观组织中包括微米级晶粒和纳米级晶粒,合金的强化方式为纳米晶强化、固溶强化以及沉淀强化,拉伸试样的断口分析表明,合金的断裂方式主要为沿晶断裂。

An Alll. 3Zn2.4Mg1. 1Cu alloy has been prepared by spray forming equipment manufactured by Ospray company. The spray-formed alloy was extruded, and then heat treated with solid solution and aging. Mechanical properties of the experimental alloy were examined by material test machine. The ultimate tensile strength, yield strength and elongation rate are 849 MPa, 796 MPa and 3.3% , respectively. Microstructures of the spray formed alloy have been investigated by transmission electron microscopy （TEM） and scanning electron microscopy （SEM）. It was shown that micron and nano-scale grains existed in the alloy, and high strength of the alloy resulted from nano-scale grains strengthening, solid solution strengthening and precipitation strengthening. Feature of fracture of the tension sample was type of intergrain fracture in terms of analyses of SEM.