目的 揭示喷砂预处理表面三维粗糙度参数对热喷涂层结合强度的影响规律。方法 以喷砂距离和喷砂速度为影响因子，对45#钢试样进行喷砂处理，采用三维光学显微镜测得各工艺参数下喷砂表面的三维形貌及三维粗糙度参数，并利用“粘接-拉伸”测试方法测得涂层的结合强度。利用回归分析方法，建立涂层结合强度与三维粗糙度参数间回归数学模型，并进一步分析三维粗糙度参数的影响机制。结果 喷砂预处理表面随机分布着许多不规则形状的凸峰和凹坑，方向各异，没有固定的取向，其整体表面粗糙度Sa平均为4.84 μm，涂层结合强度平均为32.8 MPa。涂层结合强度与三维粗糙度参数间存在着非线性相关关系，且Sa、Sdr、Sdq、Sq对涂层结合强度的影响较为显著。Sa和Sdr越大，有利于增大涂层与基体的接触面积；Sdq较大时，所形成的凹坑及凸峰较为尖锐，有利于为涂层机械结合提供更多的锚固点；结合界面的Sq较大时，其表面形貌以较深的凹坑为主，导致凹坑深处易形成残留气孔缺陷，降低涂层与基体间的润湿效果及结合性能。结论 Sa、Sdr、Sdq、Sq为涂层结合强度的主要影响因素，且存在非线性回归关系，各三维粗糙度参数对涂层结合强度的影响机制及趋势与回归数学模型一致。

The work aims to reveal the effects of three-dimensional roughness parameters of sandblasted pretreatment surface on bond strength of thermal spray coating. The effect analysis was carried out on the surfaces of 45# steel specimens, which were pretreated with sandblasting at different distances and speeds as the processing parameters. The three-dimensional topography and roughness parameters of the sandblasted surfaces were obtained by the three-dimensional optical microscope. The bond strength of thermal spraying coatings was tested with the testing methods of "bonding-stretching". Using the regression analysis method, the mathematical model between the bond strength and the three-dimensional roughness parameters of coating was established, and the effect mechanism of the three-dimensional roughness parameters was further analyzed. The results indicated that many irregular peaks and pits were randomly distributed on the sandblasted surface without fixed orientation. The average surface roughness and bonding strength of the coating were 4.84 μm and 32.8 MPa, respectively. The relationship between bond strength and 3D roughness parameters is linked by nonlinear correlation. The effect of three-dimensional roughness parameters Sa, Sdr, Sdq, Sq on the bond strength of the coating is significant. The contact area of coating with the substrate increases with the increasing of Sa and Sdr. The larger the Sdq is, the sharper the pits and peaks of the blasted surface are , which is beneficial to provide more anchor points for mechanical bonding of the coating. The surface topography of the combined interface with larger Sq mainly consists of deep pits, which leads to the formation of residual porosity defects in the depth of the pit and reduces the wetting effect and bonding performance between coating and substrate. Sa, Sdr, Sdq, Sq are the main influencing factors for bond strength of thermal spraying coating, and the regression relationship is nonlinear. The effect mechanism and trend of each three-dimensional roughness parameter on the bond strength of the coating are consistent with the regression mathematical model.