CAJ | 학술논문

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。
채용진공감응용련로제비Al-1Li、Al-2Li화Al-3Li이원합금，용금상현미경관찰기주태조직，병용DSC학정기상전변온도。대3충합금진행고용화시효처리，용유씨경도계측량시양적경도。선택구유불동시효시간적Al-Li합금진행랍신실험，병용SEM관찰단구형모。결과표명：제Al-1Li합금외，Al-2Li화Al-3Li합금구유명현시효경화화강화효응；Al-1Li、Al-2Li화Al-3Li합금적최대항랍강도분별위63 MPa、162 MPa화298 MPa；합금원소Li재제고Al-Li합금강도적동시，도치기인성강저，단렬유인성향취성전변。
Al-1Li,Al-2Li and Al-3Li binary alloys were prepared by using vacuum induction melting fur-nace. The as-cast microstructure was observed with an optical microscopy and the phase transition tempera-tures 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 mor-phologies 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.