Microstructure and mechanical properties of flame-sprayed PEEK coating remelted by laser process

Poly-ether-ether-ketone (PEEK) is one of the high-performance thermoplastics. It is being increasingly used for many industrial applications due to its excellent properties. In this paper, a flame spraying technique is used to deposit PEEK coating on 304L stainless substrates. CO2 and Nd:YAG laser treatments are chosen to remelt the as-sprayed polymer coating to get a dense coating. The microstructures of the as-sprayed and remelted coatings are characterized by SEM and XRD. The results show that both CO2 and Nd:YAG lasers are suitable for densifying the PEEK coating on stainless substrate. However, the remelted coatings present different crystalline structure due to their laser processing parameters. Hardness measurements, tribological and scratch tests are conducted to characterize the mechanical properties of remelted coating. The coatings' mechanical properties are correlated with their structures.