| 摘要 |
PURPOSE:To extend the service life of a thermally ceramic sprayed layer to the exfoliation thereof by melting and resolidifying the surface of the ceramic sprayed layer formed on a base material by using high-density energy and growing the generated fine cracks by a cold-heat cycle. CONSTITUTION:The thermally ceramic sprayed layer 3 is formed via a bond layer 2 on the surface of the base metallic material 1. The high-density energy 5 such as laser or plasma is irradiated to the surface of such sprayed layer 3. The irradiation position is moved to quickly melt the extreme surface layer 3A and thereafter, said layer is quickly solidified to form a resolidified layer 3B and to generate the many fine cracks 6. The pores 4 of the surface layer 3A are mostly annihilated in this stage. The entire part of the sprayed layer 3 is then subjected repeatedly to the cycle of heating and cooling to propagate and grow the cracks 6 to the layer 3C which is not subjected to the resolidification treatment. The fine cracks 6 having directivity function effectively to relieve the thermal stress during use. The service life of the ceramic coated member is thus extended. |
