The Investigations On Aluminium Substrates Coated With Micro-Sized WC-Co /Cr3C2 -NiCr Multi-Layered Hard Coating

The aim of this paper is to analyze the enhanced properties of aluminium substrates by coating with multilayered hard coatings. In this study, coating containing alternative filmy layers of micro-sized chrome carbide– nickel chrome (75:25) and tungsten carbide – cobalt (88:12) are coated on LM 9 aluminium substrate using high-velocity liquid fuel (HVLF) spray technique. The results indicate that multi-layered coating has shown good mechanical properties with significant improvements in the hardness and porosity with the coating strength as prescribed for use in IC engines. The mechanical properties of multilayered coating are strongly affected by number of coating layers.