Abstract:
The purpose of the study was to understand the adhesion mechanism between cold-sprayed
copper and SS316L steel substrate. Coatings of 3-mm thickness were deposited by coldspraying on steel substrates prepared with different roughness values. To understand the
bonding mechanism of the coating with substrates, scanning electron microscopy (SEM), and
energy dispersive spectroscopy (EDS) analyses were done on interfacial surfaces; exposed
after the adhesion testing. Additionally, cross-sectional as-well-as top surface deformation
behaviour of single copper particles deposited on steel substrates was investigated by using
SEM/EDS, to elucidate the mechanism behind bonding. The results of the study validated
that the adhesion is governed by both metallurgical bonding, as-well-as, mechanical
interlocking, owing to the jetting formation. The mirror-polished surface resulted in a better
adhesion strength as compared to the as-received and semi-polished surfaces, which was
further validated by ultrasonic testing. Also, smaller-sized particles were found to be
favourable for good adhesion strength.
