Synthesis and characterization of Mg-AZ91/AlN composites
Synthesis and characterization of Mg-AZ91/AlN composites
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DOI：
10.1016/j.matdes.2012.02.001
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发表时间：
2012-06
影响因子：
8.4
通讯作者：
E. Bedolla;J. Lemus-Ruiz;A. Contreras
中科院分区：
文献类型：
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作者：
E. Bedolla;J. Lemus-Ruiz;A. Contreras
本文研究了AlN （49vol.%）增强AZ91E镁合金金属基复合材料（MMCs）的合成与表征。将熔融的AZ91E镁合金在900℃无压力渗透到1450℃烧结的AlN预坯中，其孔隙率约为51vol.%。通过扫描电镜（SEM）、透射电镜（TEM）和x射线衍射（XRD）对复合材料进行了微观结构表征。评价了增强剂的分布、微观结构、反应产物及部分力学和热电性能。扫描电镜观察表明，基体和强化组织均匀。通过XRD检测AlN、Mg和mg17al12相。透射电镜观察发现存在Mg17Al12、AlN和MgO相。力学表征结果表明，弹性模量平均值为133GPa，硬度平均值为24 HRC （260HV）。在27 ~ 227℃（300 ~ 500k）范围内，热膨胀系数（CTE）为9.53×10−6°C−1。在温度为25℃时，电阻率约为45.9×106Ωcm。
This work presents the synthesis and characterization of metal matrix composites (MMCs) of magnesium alloy AZ91E reinforced with AlN (49vol.%). Molten AZ91E magnesium alloy was pressureless infiltrated at 900°C into AlN preforms sintered at 1450°C with porosities around 51vol.%. The composites obtained were microstructurally characterized through scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Reinforcement distribution, microstructure, reaction products and some mechanical and thermoelectric properties were evaluated. SEM observations showed a homogeneous microstructure of matrix and reinforcement. AlN, Mg and Mg17Al12phases were detected through XRD. TEM observations revealed the presence of Mg17Al12, AlN, and MgO precipitates. Results of mechanical characterization indicate average values of elastic modulus of 133GPa and hardness of 24 HRC (260HV). The coefficient of thermal expansion (CTE) was 9.53×10−6°C−1in the temperature range of 27–227°C (300–500K). The electrical resistivity was around 45.9×106Ωcm at temperature of 25°C.