“The coarse particles in the coating are completely unacceptable for micro-size processing,” says Liu. “When the coating is deposited using a cathodic arc process, the coarse particles of the metal phase will eventually stick to the surface of the coating. Since the micro- Remove the coarse particles by polishing, as is usually done for larger cutters.
Liu suggested that the ion-arc process can be replaced by the ion sputtering process provided by CALLOY. The ion splash is more suitable for depositing a micro-tool coating because it can deposit a smooth thin coating with no coarse particles and the coating thickness can be maintained between about 1 and 2 μm.
Liu added. The coating of cemented carbide end mills is mainly to improve the productivity. Especially for those tools used to cut difficult-to-machine materials. “If you properly coat the carbide cutting tool will improve its performance, the same for any other carbide cutting tools.”
Regardless of the technical difficulty of coating micro-tools, many commercial coating companies are hesitant about the coating of such tools, but also because of the fragile knife in the course of operation is easy to be damaged. According to Liu, in the coating process, at least three steps to the implementation of the tool, first, the tool removed from the packaging one by one, and transferred to the cleaning rack; the second is to transfer the tool to the fixture fixture; Third, the tool back into the packaging, so that shipped back to the manufacturer there. “If the coating is sent in good condition and you are damaged during the coating process, you will need compensation.
If the miniature tool manufacturer has its own coating equipment, this will not be a problem. But most manufacturers do not have such equipment. So can only rely on external resources that may be more or less damaged some of the tools. Liu estimates that there is difficulty in coating operation and coating technology. About 95% of the micro-tools are not coated.
CALLOY Tool Company outsourced the coating of its micro-tools to other companies, and Liu said it was difficult to find a company that could handle the fragile micro-tools and be willing to coat them. “The smaller the tool size, the more the coating company It is possible to damage it. “