Thermisches Spritzen von PTA-Werkstoffsystemen

在许多工业应用中，HVOF喷涂的金属陶瓷涂层用于保护免受磨料或侵蚀磨损应力。在通过压块回收钢铁粉尘的过程中，许多部件在通常组合的热负荷、磨损负荷、侵蚀负荷和机械负荷下工作。为了使热喷涂层能够在这些条件下可靠地使用，必须通过优化涂层附着力来提供对机械载荷的最大公差。此外，必须确保在高温氧化气氛下的耐磨性或耐腐蚀性。因此，主要目标是在所述条件下增加涂层结合强度，并因此增加损伤容限以避免涂层在局部过应力后剥落。通过使用根据涂层残余应力优化的喷涂参数来应用多层涂层是一种可能的方法。此外，在无应力条件下，在工作温度下进行预退火，可提高涂层系统内边界处的附着力。

In many industrial applications, HVOF-sprayed cermet coatings are used for the protection from abrasive or erosive wear stress. In the recycling of steelwork dusts by briquetting, a number of parts work under thermal, abrasive, erosive and mechanical loads which are typically combined. To enable reliable service of thermally sprayed coatings under these conditions, a maximum toler-ance towards mechanical loads must be provided by means of optimised coating adhesion. Fur-thermore, resistance against abrasives or erosives under oxidising atmospheres at elevated tem-peratures has to be ensured. Thus, the main goal is an increase in coating bond strength under the described conditions and therefore an increased damage tolerance to avoid spalling of the coating after local overstress. The application of multilayer coatings by using spray parameters that are op-timised regarding the coating residual stresses is one possible way. Additionally, enhanced adhe-sion at the inner boundaries of the coating system shall be induced by pre-annealing at working temperature under unstressed conditions.