Many industrial applications require efficient stripping methods for thermal spray coatings, especially when cost-intensive substrate materials are utilized. A typical example are turbine components with thermal barrier coatings (plasma-sprayed YSZ) in combination with nickel-based bond coatings, such as rotor blades which are condition more than five times in the turbine industry. Unfortunately, the conventional stripping methods are dirty (contamination with grid blasting material), environmentally harmful (aggressive fluids, strong acid) or relatively ineffective (high tool load in mechanical milling). In order to avoid these disadvantages alternative techniques such as removal by laser, water jet stripping and hybrid methods such as ultrasonic-based mechanical methods and a combination of water-, laser- and cryo-techniques have been investigated. In this paper newly developed stripping methods are compared to classic techniques. The evaluation considers user-friendliness and technological performance under the aspects of substrate-interaction, material emission and economic considerations.
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