| 摘要 |
PROBLEM TO BE SOLVED: To provide a thermal spray method whereby a fine spray coating film with a small surface roughness can be formed. SOLUTION: Thermal spray is conducted by thermally softening or fusing a powder material, which is fed from a feeding machine through a transport tube 16, in a thermal spray gun 11 and delivering the material. The thermally softened or fused powder material in the thermal spray gun 11 is delivered by causing it to pass through the inside of a tubular air current 20 due to a compressed gas jetted from a jetting port 18. In the feeding machine, the atmospheric pressure in the feed nozzle is set to lower than that at the vicinity of the upstream side end of the feed nozzle, thus causing the powder material to be sucked into the fed nozzle. The powder material used has such particle sizes that the particle size (D90%) at which the cumulative particle volume from the small particle size side is 90% of the total particle volume is 20 μm or lower. |
