Application of AC-HVAF in Surface Treatment of Super Mirror Roll
Super mirror roller is an indispensable and important part in the production equipment of optical-grade plastic sheet, sheet and film. It is widely used in sheet machine, tape casting machine, calender and coating machine and other equipment to carry out surface calendering treatment on metal, plastic (PVC, ABS, PP, PE, PT, PC, etc.), film, leather, paper, textile and other materials. The surface of traditional mirror roller is generally treated with hard chromium plating or plasma spraying ceramic coating, of which hard chromium plating roller has poor wear resistance and short service life; The porosity of plasma sprayed ceramic roll is relatively large (about 3%). After grinding and polishing, it can only reach the mirror level, but cannot reach the super-mirror effect.
Based on the characteristics of low flame temperature (<1800 ℃), high particle velocity (>700 m/s), dense coating structure and high bonding strength of the active combustion high-speed gas spraying (AC-HVAF), the carbide-based cermet coating is sprayed on the surface of the roller using AC-HVAF technology, and the surface roughness of the roller after grinding and polishing can reach Ra 0.01 μ M (i.e. grade 14), the service life can be increased by more than 3 times compared with the chrome-plated roller. The main performance indicators of the spray coating: porosity is less than 0.3%, binding force is more than 70 MPa, hardness is 1 300~1 450 HV, and the polished surface finish can reach level 14. The application of this technology has formed mass production.