【摘要】 通过拉伸试验机、扫描电镜、透射电镜和光学显微镜等研究了真空感应熔炼水冷铜模铸造对2024铝合金经形变热处理后组织及性能的影响。结果表明:相对于普通铸造,真空感应熔炼水冷铜模铸造可使合金显微组织得到很大程度的改善,等轴晶数目增多,晶粒得到明显细化,平均晶粒尺寸从125μm减小至28μm;经过形变热处理后,真空感应熔炼水冷铜模铸造合金的抗拉强度、屈服强度和伸长率分别达到603MPa,581MPa和12%,合金在获得高强度时仍保持较好的塑性;常规铸造合金经形变热处理后试样的拉伸断口形貌呈现脆性断裂特征,而真空感应熔炼水冷铜模铸造合金经形变热处理后试样拉伸断口形貌呈现韧性断裂特征。更多还原

【Abstract】 The effects of vacuum induction melting and copper water-cooled mould casting on microstructure and properties of 2024 aluminum alloy after thermo-mechanical treatment were studied using tensile testing,scanning electron microscopy,transmission electron microscopy and optical microscopy.The results show that compared with the conventional casting,the vacuum induction melting and copper water-cooled mould casting can improve the microstructure of 2024 alloy,including increasing the amount of equiaxed grains,refining grains and decreasing the average grain size from 125 μm to 28 μm.The tensile strength and yield strength of the alloy after thermo-mechanical treatment(TMT) prepared by vacuum induction melting and copper water-cooled mould casting reached 603 MPa and 581 MPa,the specific elongation of the alloy was up to 12.0%.The alloy had a good combination match of plasticity with strength.The fracture of conventional casting 2024 aluminum alloy presented brittle fracture mode,but the fracture of vacuum induction melting and copper water-cooled mould casting alloy presented ductile fracture mode.更多还原