摘要
采用真空感应熔炼炉制备Al-1Li、Al-2Li和Al-3Li二元合金,用金相显微镜观察其铸态组织,并用DSC确定其相转变温度。对3种合金进行固溶和时效处理,用维氏硬度计测量试样的硬度。选择具有不同时效时间的Al-Li合金进行拉伸实验,并用SEM观察断口形貌。结果表明:除Al-1Li合金外,Al-2Li和Al-3Li合金具有明显时效硬化和强化效应;Al-1Li、Al-2Li和Al-3Li合金的最大抗拉强度分别为63 MPa、162 MPa和298 MPa;合金元素Li在提高Al-Li合金强度的同时,导致其韧性降低,断裂由韧性向脆性转变。
Al-1Li,Al-2Li and Al-3Li binary alloys were prepared by using vacuum induction melting furnace. The ascast microstructure was observed with an optical microscopy and the phase transition temperatures of the three alloys were determined by differential scanning calorimetry（ DSC）. After solution and ag-ing treatment,the hardness of the three alloy samples were measured by using Vickers hardness tester. The Al-Li alloy samples were selected with different aging time and tensile test was conducted. The fracture morphologies of the samples were observed by scanning electron microscope（ SEM ）. The results indicate that both Al-2 Li alloy and Al-3 Li alloy have aging hardening and strengthening effects but Al-1 Li alloy does not. The maximum tensile strength of Al-1Li,Al-2Li and Al-3Li binary alloys are 63MPa,162MPa and 298MPa respectively. The tensile strength is increased and the toughness of Al-Li alloys is decreased with the growth of Li element. The fracture mechanism of alloys is changed to the brittle fracture from the ductile fracture due to Li addition.
出处
《沈阳航空航天大学学报》
2015年第2期48-53,共6页
Journal of Shenyang Aerospace University
基金
国家自然科学基金青年基金(项目编号:51301113)
关键词
Al-Li二元合金
力学性能
固溶
时效
Al-Li binary alloy
mechanical properties
solution treatment
aging treatment
