K. Ogawa, Tohoku University, Sendai, Japan
In recent year, many structures and devices are exposed in severe environments, such as high temperature, high pressure, complex atmosphere etc. Therefore, thermal spray coatings play a role in protection of substrate materials under such severe environments. However, in the case of exposing such environments, there is a possibility that unpredictable degradation or damage occurs. Accordingly, elucidation of the mechanism of degradation and damage of the coatings is very important. Moreover, the diagnostic of degradation and damage for the structure based on the mechanism improves the reliability and safety of the structure with coatings. In this study, reliability and safety study for thermal spray coatings, which is exposed in severe environments, is described. In particular, degradation mechanisms of the coatings and their nondestructive evaluation technique are mentioned.
Summary: In our research field, research related to the safety and reliability of materials connected with the development of materials that are durable at ultra-high temperatures over long periods of time is promoted based on the development of high efficiency plants etc. Fracture physics and chemistry is studied by elucidating degradation and damage mechanisms, especially for Ni base superalloys, thermal barrier coatings, and C/C composites etc. The drastic improvements in efficiency of high energy conversion equipment demanded by society were realized through this research, contributing to the reduction of environmental impacts. In this study, reliability and safety study for thermal spray coatings, which is exposed in severe environments, is described. In particular, degradation mechanisms of the coatings and their nondestructive evaluation technique are mentioned.
