PROTECTIVE MATERIAL FOR PROTECTING INNER WALL OF MOLD FOR CASTING TITANIUM AND TITANIUM ALLOY

摘要

PURPOSE: Provided is a protective material for protecting a mold for casting titanium and its alloy, which prevents molten metal from being adhered to a mold and avoids corrosion of a mold by forming a plasma thermal spraying layer and a coating layer on the surface of a mold. CONSTITUTION: The protective material(30) protects an inner wall of a mold for casting titanium and its alloy by the steps of: thermal-spraying plasma on the surface of a mold to form a plasma thermal-spraying layer(31); and coating the plasma thermal-spraying layer(31) with a coating material(ceramic powder) to form a coating layer(32). A material of the plasma thermal-spraying layer(31) is Ni. The ceramic powder is one selected from Y2O3, CaO, ZrO2, MgO, and Al2O3. The coating material is ceramic powder in whole, or a mixture consisting of 19.4wt% of ceramic powder, 0.4wt% of a PVB binder, and 80.2wt% of an additive, wherein a viscosity of the mixture is 4s based on zanhcup No.4.