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第三讲 高速电弧喷涂工艺及应用 一、高速电弧喷涂预处理工艺 高速电弧喷涂工艺包括工件表面的预处理、喷涂、喷后处理等几个大的步骤。高速电弧喷涂时,高压空气将喷涂材料雾化并高速沉积在工件表面。如果工件表面上带有水分、油脂和灰尘时,喷涂材料微粒与表面之间就会存在一层隔膜,不能很好地互相嵌合。如果表面光滑,微粒也会滑掉或虚浮地沉积,随着喷涂层的逐渐增厚由于内应力增大而脱落。只有洁净、干燥、粗糙的表面,才能使微粒在塑性尚未消失时与表面牢固地嵌合,形成良好的附着条件。因此,为了提高喷涂层的结合强度,对工件表面进行预处理是一个十分重要的步骤,它往往关系到整个工艺过程的成败。 工件表面预处理包括以下内容: 1.表面清洗 对待喷涂表面及其邻区进行除油、去污、除锈等清洗工作,
Lecture 3 High Speed Arc Spraying Process and Application I. High Speed Arc Spraying Pretreatment Process The high speed arc spraying process includes several major steps such as pretreatment, spraying and post-spray treatment on the workpiece surface. High-speed arc spraying, the high-pressure air spray material spray and high-speed deposition on the workpiece surface. If the workpiece surface with moisture, grease and dust, there will be a layer of membrane between the spray material particles and the surface, can not fit each other well. If the surface is smooth, the particles will either slip off or float down and fall off as the internal stress increases as the spray coating thickens. Only clean, dry, rough surface, in order to make the particles have not yet disappeared in plastic with the surface firmly fit to form a good adhesion conditions. Therefore, in order to improve the bonding strength of the sprayed coating, pretreatment of the workpiece surface is a very important step, which often relates to the success of the entire process. Workpiece surface pretreatment include the following: 1. Surface cleaning Spray the surface and its adjacent areas for oil, decontamination, rust and other cleaning work,