A formulation of water-based lost foam coating for low-temperature high-strength ductile iron

Abstract

The invention provides a formula of water-based lost foam paint for low-temperature high-strength ductile iron. The formula comprises refractory aggregate, an adhesive, a suspension agent, a surface active agent and a carrier; the refractory aggregate comprises diatomaceous earth, zircon powder, forsterite powder and flake graphite; the adhesive comprises polyving akohol and silica sol; the suspension agent comprises lithium-based bentonite and aluminum-magnesium silicate; and the surface active agent comprises a water-based defoamer, a wetting agent and a penetrating agent. The paint preparedaccording to the formula has excellent sag resistance, uniformity, thermal stability and metal oxidative corrosion resistance, and castings cast through the paint have excellent surface finish and clear outlines.

Description

technical field [0001] The invention relates to the technical field of coated sand casting coatings, in particular to a formulation of a water-based lost foam coating for low-temperature high-strength ductile iron. Background technique [0002] Lost foam casting is to combine the plastic foam model with the same size and shape as the casting and the riser system made of the same material to form a model cluster, brush the lost foam paint and dry it, and bury it in the dry sand of the special sand box Vibrating and compacting the molding, using vacuum equipment to connect a special sand box to evacuate, pouring high-temperature metal liquid under the condition of maintaining a certain negative pressure in the mold to melt and gasify the mold, and the decomposition products escape through the coating / mould interface, and the liquid state A casting method in which metal occupies the position of the model, solidifies and cools to form a casting. Lost foam casting has outstandin...

AI Technical Summary

Problems solved by technology

Although the lost foam casting process has developed rapidly since its inception, the coating technology has been plagued by the difficulty of improving the casting yield. The main reason is that the quality of the coating cannot meet the requirements of the lost foam casting process.

One is that the strength at room temperature does not meet the requirements, and the shape is deformed and the paint is damaged during molding, so that the casting is scrapped; the other is that the high-temperature strength is low, and the casting cavity collapses, damages, and paint peeling occurs during pouring, so that the casting is scrapped