COMPUTATION OF ROUGHNESS AT SUBSTRATE COATING INTERFACE ON DEPOSITION OF ALUMINIUM OVER MEDIUM CARBON STEEL BY FRICTION SURFACING

Abstract

Friction surfacing is happening to be a solid-state lining process, which proposes a mean of producing perfect coating between alike and unlike materials utilizing mechanical interlocking at the coating interface. During friction surfacing, the low rotational speed with high axial force normally produces good quality bonding; however, poor mechanical interlocking and cavitation at coating substrate interface resulted in an adverse effect on bond quality. In this present work, the substrate plate was preheated at three different temperatures of 100°C, 200°C and 300°C to create a coating of aluminium 6063 over EN8 medium carbon steel using friction surfacing. The mechanical interlocking was recognized from the specimen image of longitudinal cross-sectional slices, received from optical microscopy. Image recognition software (ImageJ) which depicts the substrate coating interface produce the interfacial roughness profile. The deepness of interlocking at coating interfacial region was monitored at different substrate preheating temperatures done by filter profile graph. The degree of interlocking has been calculated by interfacial roughness values of the profile graph by the use of Python programming language. Then this was compared with a bond strength to identify the relationship among them. Further push off and bonding strength caused by the dovetail shaped interlocking have become higher compared to narrow shaped interlocks stated by profile graph.