E. Sadri, F. Ashrafizadeh, M. Ramazani. Production and characterization of Cr2O3-Ag nanostructured composite powders in plasma spraying process. Journal of Advanced Materials in Engineering (Esteghlal) 2013; 32 (2) :101-115
URL:
http://jame.iut.ac.ir/article-1-563-en.html
Department of Materials Engineering, Isfahan University of Technology, , ehsansadri1@yahoo.com
Abstract: (7950 Views)
In plasma sprayed nanostructured composite coatings with ceramic matrix, the feedstock must consist of nanoparticles of appropriate specifications. In this research, the procedure for production of Cr2O3-Ag agglomerated nanostructured composite powder to produce comosite coatings has been investigated. Nanopowders of Cr2O3 with 0, 2, 5, and 10 volume percentages of silver were dispersed to obtain a homogeneous aqueous dispersion appropriate for spray drying process. In the second stage, Cr2O3-Ag composite powders were produced by agglomeration process. The nanostructured composite powders were, then, used in the atmospheric plasma spray (APS) process to deposit a series of composite coatings for evaluation. The composite powders, with a granulated morphology, had uniform distribution of silver in a ceramic matrix and the coatings were composed of nanoparticles and particles of nano-sized crystallites. Experimental results indicated that presence of nanoparticle zones within the microstructure led to non-uniform porosities formed between splats and these zones. Furthermore, use of nanopowders in the feedstock caused a reduction in lamellae thickness of plasma sprayed coatings.
Type of Study:
Research |
Subject:
General Received: 2015/02/9 | Accepted: 2015/05/6 | Published: 2015/05/6