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

Satish Tailor, V. K. Sharma, R. M. Mohanty, P. R. Soni

Council of Scientific and Industrial Research, CSIR-HQS, New Delhi, India..
Department of Metallurgical and Materials Engineering, Malaviya National Institute of Technology, Jaipur, India.

DOI: 10.4236/jsemat.2012.223035                

Abstract

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.

Keywords

AlSi-SiC; Attrition Milling; Plasma Spray Coating; Adhesion Strength; Wear Resistance

Conflicts of Interest

The authors declare no conflicts of interest.

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