Water erosion resistant surface treatments

通常的做法是注入水来冷却压缩机中的空气，从而增加燃气轮机的功率输出。水滴的反复撞击可能会导致翼型前缘的显著沿着腐蚀，不仅导致性能下降，而且由于气动不稳定性，还可能导致翼型的高周疲劳失效。因此，需要开发更耐水侵蚀的压缩机叶片。该项目将包括不同材料的水侵蚀机理的研究，抗水侵蚀涂层的开发，这些涂层的表征和测试。它还将包括水冲击现象的建模。不同尺寸的水滴在局部撞击表面时提供不同的动能，因此保护涂层应该坚硬，坚韧并提供疏水效果。将研究各种涂层，包括硬质纳米结构陶瓷和疏水涂层。将研究所开发的涂层的微观结构，机械和功能性能。这将包括研究基体条件（即微观结构、纹理和残余应力）对所得涂层/表面处理的微观结构、性能和耐腐蚀性的影响。耐腐蚀性试验将在按照ASTM G73-04标准（液体冲击腐蚀试验的标准实践）设计的专用试验台上进行，并进行调整以模拟压缩机内部的操作条件。在该试验台上，可以确定材料和涂层/表面处理的耐腐蚀性或其他损坏性;研究损坏机制以及水滴的大小、速度和频率如何影响损坏机制。通过这种方式，我们将能够研究叶片材料的水蚀行为和动态机械性能之间可能的相互作用。

Injecting water to cool the air in the compressor hence increasing the power output of the gas turbines is a common practice. Repeated impacts of water droplets maycause significant erosion along the leading edges of the airfoils resulting not onlyin performance degradation but also in potential for high-cycle fatigue failure of the airfoils due to aerodynamic instability. Consequently, there is a need to develop a more water erosion resistant compressor blades. This project will include the studyof water erosion mechanism of different materials, development of coatings resistant to water erosion, characterization and testing of these coatings. It will also include modeling of the water impingement phenomenon. Different sizes of water droplets provide various kinetic energywhile locally hitting the surface, thus protective coatings should be hard, tough and provide the hydrophobic effect. Various coatings will be studied including hard nanostructure ceramic and hydrophobic coatings. The microstructure, mechanical and functional properties of the developed coatings will be studied. This will include the investigation of the effect of substrate conditions (i.e. microstructure, texture and residual stresses) on the microstructure, properties and erosion resistance of the resulting coating/surface treatment. Testing of erosion resistance will be performed on a special rig designed as per ASTM G73-04 standard (Standard Practice for Liquid Impingement Erosion Testing) and adjusted to simulate the operating conditions inside the compressor. Inthis test rig, it will be possible to determine the resistance to erosion or other damage of the materials and coatings/surface treatments; to investigate the damage mechanisms and how theyare influenced bythe size, velocityand frequencyof water droplets. In this way, we will be able to studya possible interaction between water erosion behaviour and dynamic mechanical properties of the blades materials.