Tribological and engine performances of plasma sprayed partially stabilized zirconia PSZ alumina coatings on A1 Si piston alloy

Abstract

In general, the Aluminium Alloy (AA) 6000 series is named as the newlineAluminium-Silicon (Al-Si) alloy or the piston alloy, which is widely used in newlineseveral engine components of the automobiles due to its high strength to density newlineratio. During piston-cylinder mechanism, the piston material should resist the newlinewear while sliding against the cast iron cylinder walls and simultaneously, it newlineshould withstand a high temperature above 300°C inside the chamber. Therefore, newlinethe wear and thermal resistance of the Al-Si alloy need to be improved. Thermal newlineBarrier Coatings (TBCs) are capable to withstand in a high temperature around newline1200°C and also it can provide a resistance to the wear. The application of TBC newlineon piston is done previously by the earlier researchers. The widely used TBC newlinematerial is Yttria3 mol. % Partially Stabilized Zirconia (3Y-PSZ), because of its high newlinedurability, hardness, fracture toughness, chemically inert and temperature radiant. newlineAlumina (Al2O3) could be integrated with PSZ to improve the bonding strength. newlineFrom the literature, it is inferred that the integration of 3Y-PSZ with Al2O3 newlinefor TBC is not done yet. Hence, the present research work focuses to integrate the newline3Y-PSZ and Al2O3 for TBC in piston application. The 3Y-PSZ and Al2O3 are newlineintegrated as multilayer, composite and fused TBCs are done on the Al-Si alloy newlineusing the plasma spray technique. The thermal, wear and engine performances of newlinethe TBCs are studied and their results are compared. newlineFor the current study, the 3Y-PSZ (ZO) and Al2O3 (AO) coatings on the newlineAl-Si alloy (cuboid, pellets, pin and piston) are done as mono layers (ZO and AO), newlinethe bi-layers (ZO-AO and AO-ZO), the ZO/AO Composite (ZAC) layer and the newlineFused ZO/AO (FZA) layer by using the plasma spray setup (Model: METCO) at newlinethe constant process condition. Al20Cr20Ni60 is selected as the bond coat for all the newlineselected coatings on the Al-Si alloy. The average coating thickness of top coat is newlinearound 250 and#956;m and the bond coat is around 250 and#956;m, i.e., totally around 500 and#956;m newlineof coating thickness. newline