Li Chuan-Peng, Wang Zhi-Guo, Zha Min, Wang Cheng, Yu Hong-Chen, Wang Hui-Yuan, Jiang Qi-Chuan
State Key Laboratory of Automotive Simulation and Control, Key Laboratory of Automobile Materials of Ministry of Education & School of Materials Science and Engineering, Nanling Campus, Jilin University, No. 5988 Renmin Street, Changchun 130025, China.
Center of Analytical and Testing, Beihua University, No. 3999 Binjiang East Road, Jilin 132013, China.
Materials (Basel). 2016 Nov 26;9(12):964. doi: 10.3390/ma9120964.
Nano-SiC particulates (n-SiC) reinforced Mg-8Al-1Sn (AT81) composites with different pre-oxidation parameters were fabricated by powder metallurgy (P/M) process combined with hot extrusion. The effects of pre-oxidization treatment of n-SiC on the microstructure and tensile properties of 0.5 vol % n-SiC/AT81 composites were investigated accordingly. The distribution of n-SiC with different pre-oxidation parameters was homogeneous in the composites. Moreover, it was found that a thin MgAl₂O₄ layer formed at the interface when the n-SiC were pre-oxidized at 1073 K for 2 h, while the MgAl₂O₄ layer became much thicker with pre-oxidization temperature increasing to 1273 K for 2 h. After an appropriate pre-oxidization treatment of n-SiC at 1073 K for 2 h, the as-extruded 0.5 vol % n-SiC/AT81 composites exhibited an enhanced strength. It was found that the yield strength (YS) and ultimate tensile strength (UTS) increased from 168 MPa and 311 MPa to 255 MPa and 393 MPa compared with the as-extruded AT81 alloy, reflecting 51.8% and 26.4% increments, respectively. The improvement of mechanical properties should be mainly attributed to the grain refinement and homogeneous distribution of n-SiC in the composites. Moreover, a well-bonded interface and the formation of an appropriate amount of interfacial product (MgAl₂O₄) benefited the material's mechanical properties.
采用粉末冶金（P/M）工艺结合热挤压制备了具有不同预氧化参数的纳米碳化硅（n-SiC）颗粒增强Mg-8Al-1Sn（AT81）复合材料。据此研究了n-SiC的预氧化处理对0.5 vol% n-SiC/AT81复合材料微观结构和拉伸性能的影响。在复合材料中，具有不同预氧化参数的n-SiC分布均匀。此外，研究发现，当n-SiC在1073 K下预氧化2 h时，在界面处形成了一层薄的MgAl₂O₄层，而随着预氧化温度升至1273 K并保持2 h，MgAl₂O₄层变得更厚。对n-SiC进行适当的1073 K、2 h预氧化处理后，热挤压态的0.5 vol% n-SiC/AT81复合材料强度增强。研究发现，与热挤压态的AT81合金相比，其屈服强度（YS）和抗拉强度（UTS）分别从168 MPa和311 MPa提高到255 MPa和393 MPa，增幅分别为51.8%和26.4%。力学性能的改善主要归因于复合材料中n-SiC的细化和均匀分布。此外，良好结合的界面和适量界面产物（MgAl₂O₄）的形成有利于材料的力学性能。
