Microstructure, Adhesion and Wear of Plasma Sprayed AlSi-SiC Composite Coatings

Al-12.5 wt% Si alloy powder with 15 wt% SiCp was mechanically alloyed (MA) using attrition mill in purified nitrogen atmosphere. The MA processed powder was found to have nano grain size and uniform distribution of SiCp in the AlSi matrix. This MA processed powder was used for atmospheric plasma spraying (APS) for varying distances and currents densities. The coatings obtained were studied by image analyzer, SEM and XRD. Microhardness and wear rate of the coatings were evaluated using Vickers indenter and pin on disk type tribometer, respectively. Adhesion strength of the coatings was measured by interfacial indentation test. The results showed that these coatings have uniform distribution of reinforced SiC particles in the nano crystalline matrix, low porosity (1% - 2%), low wear rates and improved adhe-sion strength. It was also observed that by increasing current density of APS, the adhesive strength increased.

碱溶ICP-AES法同时测定AlSi/SiC复合材料中的高含量硅和低含量镁、钛、铁

本文采用碱溶 ICP- AES法对 Al Si/Si C复合材料中的高含量硅和低含量镁、钛、铁的测定进行研究 ,着重进行基体元素铝及待测定元素硅、镁、钛、铁之间的干扰试验 ,进行了碱度试验和酸度试验 ,测定了Al Si/Si C复合材料中的硅、镁、钛、铁含量 ,得到了较好的精密度和准确度。方法简便可靠 ,可获得满意的分析结果。

航空航天用电子封装材料及其发展趋势

随着航空航天领域的迅速发展,其应用的电子器件不断微型化、高度集成化,并且可靠性要求越来越高,其电子封装材料具有更高的热导率及与芯片热膨胀系数的匹配性,还要求其电子封装材料具有更低的密度。BeO、AlN、Al/SiC与AlSi由于具有高热导率、低密度及与芯片材料良好的热膨胀匹配性,非常符合航空航天用电子封装材料的发展趋势,并已经逐步在取代常用的一些封装材料。重点介绍了四种材料的性能优势,以及它们之间的性能对比与应用前景分析。