Effect of Mica on the Wettability of Coatings

In the process of lost foam casting, the effective application of coating containing mica is very important. Mica coating enables the mold to form a layer of coating on its surface when it is in foam pattern, which plays the role of "protection", "support" and "isolation". During liquid metal filling, the first is the transport of high-temperature decomposition products of foam pattern through the coating. Its transmission is affected by the type and quantity of decomposition products, coating characteristics and pressure. The coating layer containing mica component should not only separate the metal liquid that has replaced the foam pattern from the dry sand without binder behind it, but also form a "barrier" between molding sand and metal liquid to prevent sand sticking; What is more important is to keep the cavity stable while allowing the products of thermal decomposition of the pattern (including liquefied objects and vaporized objects) to pass smoothly. If the liquid decomposition products of the liquefied pattern can seep out through the coating in time, it is undoubtedly very beneficial to the smooth filling of the mold and the guarantee and improvement of the casting quality
Therefore, EPC coating should have good coating properties, and be easy to apply a certain thickness of mica coating on the surface of foam pattern; At the same time, it is hoped that the paint coating mixed with mica powder will have a good wettability to the liquefied products of foam pattern, which is beneficial to the discharge of liquefied products through the coating to ensure the quality of castings. In view of the foam pattern used in the actual production of towel, the wood project focused on the influence of mica on the coating performance and the influence of the coating layer on the wettability of the liquefied products of the foam pattern.