【摘要】 本研究制备了铸态和热挤压态Mg_93-x-Co-Y₆-Sn_x（at.%）（x=0,0.5,1.0,2.0）合金，测量了其拉伸强度，并采用X射线衍射仪（XRD）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）对其微观组织进行了表征。实验表明，当Sn含量为0.5 at.%时，铸态和热挤压态合金的极限抗拉强度分别达到峰值～200.2 MPa和383.9 MPa,屈服强度分别达到峰值～199.0 MPa和355.5 MPa,伸长率分别达到峰值1.042%和2.338%,继续添加Sn元素，含量为1.0 at.%及以上时，合金的极限抗拉强度、屈服强度和伸长率均下降。在Mg_92.5-Co-Y₆-Sn_0.5（at.%）合金中，细小弥散分布的Mg₂₄Y₅相、18R-LPSO相、MgYCo₄相和Sn₃Y₅相四类析出相在其强化机制中发挥着关键作用。更多还原

【Abstract】 As-cast and hot-extruded Mg_93-x-Co-Y₆-Sn_x（at.%）with varying Sn concentration（x=0, 0.5, 1.0, 2.0） alloys were prepared. Their tensile strengths and microstructures were investigated using X-ray diffractometer（XRD）, scanning electron microscope（SEM） and transmission electron microscope（TEM）. The experiments revealed that when the Sn content was 0.5 at.%, the as-cast and hot-extruded alloys reached their peak ultimate tensile strengths of approximately 200.2 MPa and 383.9 MPa, respectively. The yield strengths peaked at around 199.0 MPa and 355.5 MPa, while the elongations reached maximum values of 1.042% and 2.338%, respectively. However, with further Sn addition at 1.0 at.% and above, the alloy exhibited a decline in ultimate tensile strength, yield strength, and elongation. respectively. The four types of fine and uniformly distributed particles, Mg₂₄Y₅, 18R LPSO, MgYCo₄ and Sn₃Y₅ phases, played a crucial role in the strengthening mechanism of the Mg_92.5-Co-Y₆-Sn_0.5（at.%） alloy in both as-cast and hot-extruded states.更多还原