摘要
采用对掺法制备了铸态Mg-9Li-3Al-2Sr-xY(x=0,2.5)合金,研究了元素钇对合金组织和拉伸性能的影响。结果表明:Mg-9Li-3Al-2Sr合金由α-Mg、β-Li、Al4Sr相组成,Al4Sr相主要分布在β-Li相中;Mg-9Li-3Al-2Sr-2.5Y合金主要由α-Mg、β-Li、Al4Sr和Al2Y相组成,Al4Sr相主要分布在β-Li相中,而Al2Y相则弥散分布在基体中;与Mg-9Li-3Al-2Sr合金相比,Mg-9Li-3Al-2Sr-2.5Y合金的抗拉强度变化不大,但伸长率提高了17.3%;Mg-9Li-3Al-2Sr合金的断裂机制为典型的沿晶断裂,而Mg-9Li-3Al-2Sr-2.5Y合金的断裂机制则是以脆性断裂为主,并伴有韧窝的混合型断裂。
As-cast Mg-9Li-3Al-2Sr-xY （x=0,2.5 ）alloys were prepared through mixture method,the influences of yttrium element on microstructure and tensile properties of Mg-9Li-3Al-2Sr alloy were studied.The results show that Mg-9Li-3Al-2Sr alloy was mainly composed ofβ-Li,α-Mg and Al4 Sr phases,and Al4 Sr phase was mainly distributed inβ-Li phase;Mg-9Li-3Al-2Sr-2.5Y alloy was mainly composed ofβ-Li,α-Mg,Al4 Sr and Al2 Y phases,Al4 Sr phase mainly distributed inβ-Li phase and Al2 Y phase diffusely distributed in the matrix.Compared with Mg-9Li-3Al-2Sr alloy,the tensile strength of Mg-9Li-3Al-2Sr-2.5Y alloy changed a little,but elongation increased by 17.3%.Fracture mechanic of Mg-9Li-3Al-2Sr alloy mainly was intergranular fracture,while the fracture mode of Mg-9Li-3Al-2Sr-2.5Y alloy mainly was a mixture of main brittle fracture and dimple characteristics.
出处
《机械工程材料》
CAS
CSCD
北大核心
2016年第12期9-12,共4页
Materials For Mechanical Engineering
基金
中央高校基本科研业务费资助项目(106112015CDJXY130011)
国家科技部国际合作项目(2010DFR50010)
关键词
镁锂合金
稀土元素钇
显微组织
拉伸性能
Mg-Al alloy
rare earth element yttrium
microstructure
tensile property
