CAJ | 학술논문

利用光学显微镜(OM)、扫描电子显微镜(SEM)、X 射线衍射仪(XRD)分析了 Li 元素对 Mg-x Li-3Al 合金组织的影响,并用电子万能试验机测试合金的拉伸性能.结果表明,Li 含量的变化可以明显改变合金的相组成.当 m (Li)＜5．7％(质量分数)时合金由单一α-Mg 相组成；Li 含量在5．7％~10．3％(质量分数)之间时,合金为α-Mg＋β-Li 双相；m (Li)＞10．3％(质量分数)时合金为单一β-Li 相.合金的塑性随 Li 含量的升高而增加,铸态 LA113合金的延伸率高达37．36％,但挤压态下合金强度随 Li 含量升高而降低,挤压态 LA53合金具有最佳抗拉强度,达到263．28 MPa.当 Li 含量升高,合金中的第二相粒子会出现 Al12 Mg17转变为 LiMgAl2.
이용광학현미경(OM)、소묘전자현미경(SEM)、X 사선연사의(XRD)분석료 Li 원소대 Mg-x Li-3Al 합금조직적영향,병용전자만능시험궤측시합금적랍신성능.결과표명,Li 함량적변화가이명현개변합금적상조성.당 m (Li)＜5．7％(질량분수)시합금유단일α-Mg 상조성；Li 함량재5．7％~10．3％(질량분수)지간시,합금위α-Mg＋β-Li 쌍상；m (Li)＞10．3％(질량분수)시합금위단일β-Li 상.합금적소성수 Li 함량적승고이증가,주태 LA113합금적연신솔고체37．36％,단제압태하합금강도수 Li 함량승고이강저,제압태 LA53합금구유최가항랍강도,체도263．28 MPa.당 Li 함량승고,합금중적제이상입자회출현 Al12 Mg17전변위 LiMgAl2.
Effects of Li addition on the microstructure of Mg-3Al based alloys were studied by optical microscope (OM),scanning electron microscope (SEM)and X-ray diffractometer (XRD).The tensile properties of as-cast and as-extruded Mg-x Li-3Al alloys were conducted at ambient temperature on an electro-universal testing ma-chine (Instron 5569).The results show that lithium content in Mg-Li alloy was a key factor affecting the micro-structure and properties of this series alloys.When it was between 5.7%-10.3wt%,Mg-Li alloy exhibits two phases structure which consists of α (hcp)Mg-rich and β (bbc)Li-rich phases.The elongation of alloys im-proves significantly with the increase of Li content and the as-cast LA1 13 alloy obtains the optimal elongation of 37.36%.But the tensile strength of as-extruded Mg-x Li-3Al alloys decrease with the increase of Li content and the as-extruded LA53 alloy obtains the optimal tensile strength of 263.28 MPa.As Li content increases,the sec-ond-phase particle Al1 2 Mg1 7 transforms into LiMgAl2 in Mg-Li alloys.