High-velocity oxygen fuel thermal spraying is widely used in industrial production, and coating hardness and density are closely related to the flight velocity of particles. In this study, the particle image velocimetry method was used to evaluate the velocity of particles produced by a JP5000 spray gun. The spraying parameters (total flow rate and equivalence ratio) on particle velocity and flight angle were studied. Both the total flow rate and equivalence ratio had effects on the particle velocity; however, the total flow rate demonstrated a greater effect. In the free jet state, the variation trend of particle velocity on the centerline exhibited a rapid increase, deceleration at 13 mm, and undulating rise to the maximum velocity before a linear decrease. The axial position of the maximum velocity increased with increasing total flow rate. In the impinging jet state, the particle velocity reached a maximum value at axial distance 13 mm from the nozzle exit (when total flow rate changed from 0.0199 to 0.0273 kg/s), and then decreased slowly, with a rapid decrease before 10 mm from the substrate. This study on particle velocity can provide guidance for optimization of the spraying process.

高速氧燃料热喷涂在工业生产中应用广泛，涂层硬度和密度与颗粒的飞行速度密切相关。在这项研究中，粒子图像测速方法用于评估 JP5000 喷枪产生的粒子的速度。研究了喷雾参数（总流量和当量比）对粒子速度和飞行角度的影响。总流量和当量比均对粒子速度有影响；然而，总流量显示出更大的影响。在自由射流状态下，中心线上的粒子速度变化趋势呈现快速增加，在13 mm处减速，并在直线下降前呈波浪状上升至最大速度。最大速度的轴向位置随着总流量的增加而增加。在撞击射流状态下，粒子速度在距喷嘴出口轴向13 mm处（总流量从0.0199变为0.0273 kg/s时）达到最大值，然后缓慢下降，10 mm前快速下降。基板。对粒子速度的研究可为喷涂工艺的优化提供指导。