Synthesis and characterization of copper based spinel coating on alumina substrate for spark plug aero-engine application
Subject Areas : journal of New MaterialsRaziyeh Arabahmadi 1 , Navid Rezaie 2 , Mojtaba Ghatee 3
1 - Chemistry Department,Payame Noor University (PNU), Tehran 19395-3697, Iran
2 - Department of Chemistry and Materials Engineering, Shahrood University of technology
3 - Department of Chemistry and Materials Engineering, Shahrood University of technology
Keywords: mechanical properties, Spinel coating, Spark plug, aero-engine, Electrical properties,
Abstract :
Abstract
The present study aims to synthesis and characterization of spinel coating for spark plug aero-engine application. At first spinel coatings were synthesized by mechanical alloying. The different spinel coatings with spinel different composition and modulation were applied on alumina substrate. The phase content of the samples was characterized by X-ray diffraction (XRD) method. The microstructure and thickness of the coatings were analyzed by scanning electron microscopy. Nano-hardness and Young’s modulus of the coating were measured by nano-indentation method. The electrical resistance of the coating was studied at different temperatures. The electrical wear resistance of the coating was evaluated by spark method. The XRD method confirmed the synthesis of copper based spinels. The coatings had a thickness of 19-22 μm with proper density. The average nano-hardness of the coatings was 10 GPa. The wear rate after 140000 of spark was less than 1% of coating weight. It was also found that the optimum modulation of the multilayer coating is 4 successive layers composed of CuFe2O4+CuCr2O4, followed by two layer of CuCr2O4 and again CuFe2O4+CuCr2O4 layer. The ratio of the components in the composite layers were 50:50 wt.%
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