Coating of pistons with ZrO2 and TaC improves their longevity and performance
in internal combustion engines by enhancing resistance to wear, heat, and
corrosion. In this study plasma spray coating is performed on crown of the
piston with the combination of the percentage composition namely, 95 % ZrO2
+ 5% TaC, 98 % ZrO2 + 2% TaC and 100% ZrO2. Among the three 95% ZrO2 + 5 %
TaC composition shows better results. The increase in ZrO2 content leads to
the formation of a more integrated scale with fewer pores. Higher
concentrations of ZrO2 in the coatings lead to increased interaction with
discharge sparks and instability of the process. At elevated temperatures, a
two-phase material of cubic zirconium dioxide and hexagonal corundum was
formed. The bonding strength of the coating is influenced by the addition of
TaC and the power input during the spraying operation. The microstructure of
ZrO2 and TaC coatings on aluminium alloy is characterized by granular
structure, tightly packed pores, and partially melted ZrO2 particles. The
coating had a uniform structure with columnar and cluster-like elements,
influenced by ZrO2 concentration.