High velocity sprayed Cr₃C₂-NiCr coatings are a viable solution to improve the life of power plant components and are often influenced by the choice of processing conditions. The new generation convertible high-velocity air-fuel (HVAF) process offers higher versatility to spray wide ranging particle sizes including the standard high-velocity oxy-fuel (HVOF) grade. However, the use of such oxygenated spraying termed as ‘HVAF(O)’ mode necessitates better understanding for reliable and repeatable coating. Single particle splat morphology and fracture mechanisms of HVAF and HVAF(O) sprayed Cr₃C₂-NiCr coatings were correlated with the microstructural features, mechanical properties and erosion performance with two different particle sizes. Among the coatings studied, HVAF(O) sprayed coarse Cr₃C₂-NiCr and HVAF sprayed fine Cr₃C₂-NiCr provided the least thermal degradation, and better mechanical properties which collectively ensured enhanced erosion performance. The overall coating performance can be attributed to the appropriate choice of process conditions and suitable particle size. In comparison with conventional HVOF process that generally induces a certain degree of thermal degradation within the hard carbides, oxygenated HVAF(O) sprayed Cr₃C₂-NiCr coating still retained most of the starting carbide phase with minimal thermal degradation, which resulted in superior erosion performance.

高速喷涂 Cr ₃ C ₂ -NiCr 涂层是提高发电厂部件寿命的可行解决方案，并且通常受加工条件选择的影响。新一代可转换高速空气燃料 (HVAF) 工艺提供了更高的多功能性，可喷涂范围广泛的颗粒，包括标准高速氧燃料 (HVOF) 等级。然而，使用这种被称为“HVAF(O)”模式的含氧喷涂需要更好地理解可靠和可重复的涂层。HVAF 和 HVAF(O) 喷涂 Cr ₃ C _{2的单颗粒飞溅形态和断裂机理}-NiCr涂层与两种不同粒径的微观结构特征、机械性能和侵蚀性能相关。在所研究的涂层中，HVAF(O) 喷涂粗 Cr ₃ C ₂ -NiCr 和 HVAF 喷涂细 Cr ₃ C ₂ -NiCr 提供了最少的热降解和更好的机械性能，共同确保了增强的侵蚀性能。The overall coating performance can be attributed to the appropriate choice of process conditions and suitable particle size. 与通常在硬质碳化物内引起一定程度的热降解的传统 HVOF 工艺相比，氧化 HVAF(O) 喷涂 Cr ₃ C ₂-NiCr 涂层仍然保留了大部分起始碳化物相，热降解最小，这导致了卓越的侵蚀性能。