Deposition of PEEK coatings using a combined flame spraying–laser remelting process

Thermoplastic coatings are of great interest for industrial applications. In the present work, PEEK (poly-ether-ether-ketone) coatings were prepared on Al and stainless steel substrates using a flame spraying technique. The as-sprayed coating, however, was simply an accumulation of the PEEK powders. It presented a high porosity and, hence, bad mechanical properties. In order to obtain a dense coating, a laser treatment was chosen to remelt the polymer coating. Nd:YAG and CO2 lasers were introduced in this work. The results show that the CO2 laser is more suitable for densifying the PEEK coating. The PEEK coating deposited on stainless steel could be densified by the CO2 laser. This indicates that it is feasible to obtain a dense PEEK coating by this combined flame spraying–laser remelting process. The laser-treated coating exhibits an amorphous structure. There was no obvious chemical modification observed on the PEEK after the flame spraying process and the laser treatment.