High-velocity oxy-fuel (HVOF) is a widely used thermal spray technique to obtain high density, high bond strength, and improved hardness coatings. In the present work, optimization of HVOF process parameters was carried out using the Taguchi method to minimize porosity and improve microhardness, and bond strength of Cr₂O₃ coatings. Based on the signal-to-noise ratio and analysis of variance, the significance of each process parameter and optimum parameter combination is obtained. Based on the signal-to-noise ratio, the most significant process parameter affecting porosity and microhardness was standoff distance, while for bond strength, it was powder feed rate. An optimal combination of process parameters for porosity, microhardness, and bond strength was obtained from S/N ratio analysis. For porosity, optimal parameters were standoff distance of 100 rpm, powder feed rate of 30 g/min, and gun speed of 250 mm/s. The optimal process parameters for microhardness were standoff distance of 300 rpm, powder feed rate of 50 g/min, and gun speed of 200 mm/s. Finally, for bond strength, the optimal process parameters were standoff distance of 300 rpm, powder feed rate of 50 g/min, and gun speed of 250 mm/s. Statistical results for porosity, microhardness, and bond strength showed that the difference between the predicted R² and adjusted R² values were relatively minimal and close to the one highlighting the fitness of the regression model employed for analysis. Fracture analysis after bond strength test showed combined adhesion/cohesion type failure for the Cr₂O₃ coatings.

高速氧燃料 (HVOF) 是一种广泛使用的热喷涂技术，可用于获得高密度、高结合强度和更高硬度的涂层。在目前的工作中，使用田口方法优化 HVOF 工艺参数，以最大限度地减少孔隙率并提高显微硬度和 Cr ₂ O _{3 的}结合强度涂料。根据信噪比和方差分析，得到各工艺参数和最佳参数组合的显着性。根据信噪比，影响孔隙率和显微硬度的最重要工艺参数是间隔距离，而对于结合强度，则是粉末进料速率。从信噪比分析中获得了孔隙率、显微硬度和结合强度的工艺参数的最佳组合。对于孔隙率，最佳参数为 100 rpm 的间隔距离、30 g/min 的送粉速度和 250 mm/s 的喷枪速度。显微硬度的最佳工艺参数是间隔距离为 300 rpm，送粉速度为 50 g/min，枪速度为 200 mm/s。最后，对于粘合强度，最佳工艺参数是 300 rpm 的间隔距离，送粉速度为 50 克/分钟，喷枪速度为 250 毫米/秒。孔隙率、显微硬度和结合强度的统计结果表明，预测值之间的差异R ²和调整后的R ²值相对最小并且接近于突出用于分析的回归模型的适合度的值。结合强度测试后的断裂分析表明 Cr ₂ O ₃涂层的结合粘附/内聚型失效。