| Journal: | Journal of the Brazilian Society of Mechanical Sciences |
| Database: | PERIÓDICA |
| System number: | 000312054 |
| ISSN: | 0100-7386 |
| Authors: | Marques, Paulo Villani1 Trevisan, Roseana da Exaltacao2 |
| Institutions: | 1Universidade Federal de Minas Gerais, Departamento de Engenharia Mecanica, Belo Horizonte, Minas Gerais. Brasil 2Universidade Estadual de Campinas, Departamento de Engenharia de Manufatura, Campinas, Sao Paulo. Brasil |
| Year: | 2000 |
| Volumen: | 22 |
| Number: | 3 |
| Pages: | 379-387 |
| Country: | Brasil |
| Language: | Inglés |
| Document type: | Artículo |
| Approach: | Experimental |
| English abstract | Self-fluxed nickel alloys are usually flame fused after thermal spraying. However, due to the practical aspects of high temperatures reached during flame fusing, large structures such as the hydraulic turbines for power generation, can not be efficiently coated. An alternative is to fuse the sprayed coating with a gas tungsten electric arc. In this case, heating is much more intensive and substrate temperature during and after the fusing operation is much lower, thus reducing the possibility that any problem will occur. In this work, coatings of self-fluxed nickel alloy fused by flame and gas tungsten arc were evaluated as protection of hydraulic turbines against cavitational damage. Several tests were performed, including the ASTM ultrasonically vibration-induced cavitation, optical and scanning electronic microscopic metallography, and hardness tests. The results showed that the arc-fused coating presented better cavitation damage resistance, probably due to its finer microstructure. A field application of this new technique is also described. A self-fluxed Ni alloy was flame sprayed in critical regions of Francis-type hydraulic turbine blades and fused by a gas tungsten arc after spraying. The blades will be inspected during the next two years |
| Disciplines: | Ingeniería |
| Keyword: | Ingeniería industrial, Ingeniería mecánica, Ingeniería metalúrgica, Turbinas hidráulicas, Revestimientos, Aleaciones, Níquel, Desgaste, Daño, Aspersión térmica |
| Keyword: | Engineering, Industrial engineering, Mechanical engineering, Metallurgical engineering, Hydraulic turbines, Coatings, Alloys, Nickel, Wear, Damage, Thermal spray |
| Full text: | Texto completo (Ver HTML) |
