Ceramic / plastic composite powder (ceraplas powder) has been produced by Fluidized-bed granulation process (FG process) by varying the binder. Alumina (Al 2 O 3 ) has been used as ceramics and Polyphenylene-sulfide (PPS) has been used as plastics. PPS has high heat and corrosion-resistant performance. Moreover, sprayed composite coatings have been evaluated by the observation of the coating microstructure, the thermal analysis, the corrosion test and the abrasive wear test. It has been recognized that sprayed composite coatings produced by FG powder have high corrosion-resistance and good wear resistance

Polyetherether-ketone (PEEK) and Polyphenylene-sulfide (PPS) are high performance thermoplastics having high heat resistance and high corrosion resistance. Composite powders of PEEK / Alumina (Al 2 O 3 ) with different Al 2 O 3 content have been produced by four processes, which are Mixing (MX) process. Mechanical granulation (MG) process. Melting-crush (MC) process and Heating-granulation (HG) process. PEEK / Al 2 O 3 composite powders have been sprayed with High Velocity Air Fuel (HVAF) spray system. The microstructures of these composite coatings have been evaluated and the properties of these composite coatings have been investigated by the corrosion test, the adhesion test, the ACT-JP test and the abrasive wear test. It was recognized that all the composite coatings containing Al 2 O 3 powder have a good wear resistance. PPS / Al 2 O 3 composite powders have been sprayed with HVAF spray system onto substrate of various pre-heat temperature. It was recognized that the adhesion strength of the composite coatings increases with increasing pre-heat temperature of substrate.

Polyphenylene-sulphide (PPS) and polyphenyletheretherketone (PEEK) have high heat and corrosion-resistant performance. Thermal sprayed coatings of PPS and PEEK have been produced by the HVAF spray system. The molecular structures of these coatings have been analyzed by Fourier Transform Infrared Spectrophotometer (FT-IR) and Differential Scanning Calorimeter (DSC). The microstructures of cross-section and surfaces of these coatings have been observed. The formation mechanism of these coatings has been estimated as follows; (1) PPS and PEEK powders are melted and oxidized during thermal spraying. However, the amount of coating oxidation is very small, so that high anti-corrosion performance of sprayed coatings is obtained. (2) These coatings have some pores including the incomplete melting particles. However, it is estimated that these pores are closed-pores.

Thermal sprayed coatings of polypenylene-sulphide (PPS) and polyphenyletherether-ketone (PEEK) have been produced by HVAF spray system. The properties of these coatings have been investigated by corrosion test and FT-IR analysis. The main results of this study are summarized as follows; (1) In case of PPS coatings, PPS powder is oxidized during thermal spraying. However, PPS coatings have a good corrosion resistance. However, PEEK coatings have high porosity so that corrosion of the substrate occurs. (2) In case of PEEK coatings, the molecular structure of PEEK powder is not changed during thermal spraying.