Development of ultra-strong adhesive strength coatings using cold spray

In the cold spray process, adhesive strength between coatings and substrates is considered to be the most crucial mechanical property. Bonding is an important factor in determining if cold spray can be used for an application. Therefore, development of effective bonding between coatings with various substrates is essential to cold spray processing. In this study, Cu coatings were deposited on to three different substrates: Al5052, Al6063, and stainless steel 316 L. The adhesive strength of Cu coatings on these three substrates was investigated. The experimental results showed that effective bonding could be generated only when particle velocity exceeds 500 m/s for Al alloy substrates, and 800 m/s for stainless steel 316 L substrates. Based on the present studies, an ultra-strong bonding (more than 200 MPa) between dissimilar materials has been developed with cold spray processing.