A water-based coating for lost foam casting

Abstract

The invention discloses a water-based coating for lost foam casting, and the coating comprises the following components by weight percent: 15-18% of 150-200-mesh porzite powder, 5-8% of 80-150-mesh quartz powder, 12-18% of 200-320-mesh bauxite, 1.2-1.5% of silica sol, 1.5-3.0% of polyvinyl acetate emulsion, 0.1-0.4% of sodium carboxymethylcellulose, 0.15-0.35% of sodium alkylbenzene sulfonate, 0.15-0.35% of sodium sulfate, 0.1-0.3% of n-octanol, 0.10-0.18% of fatty alcohol polyoxyethylene ether and the balance water.

Description

technical field [0001] The invention relates to the field of casting, in particular to the field of coating for lost foam casting. Background technique [0002] With its unique advantages, lost foam casting is known as "green casting technology" and "21st century casting technology". Since its application in my country in the 1960s, after decades of continuous development, the application field of lost foam casting has been continuously expanded, and good economic and social benefits have been obtained. [0003] Lost foam casting coating is one of the two key technologies of lost foam casting process. The performance of the coating directly affects the quality of the casting, which is significantly different from the traditional sand casting coating. The main purpose of traditional sand casting coatings is to prevent castings from mechanical sand sticking and chemical sticking sand, while coatings for lost foam casting have an important role in forming and maintaining cast...

AI Technical Summary

Problems solved by technology

[0004] Although the lost foam casting process has developed rapidly since its inception, the coating technology has been plagued by the fact that it is difficult to greatly improve 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 coating 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; the third is that the coating is not suitable. High temperature air permeability, too high air permeability will cause the cavity to collapse, and too low air permeability will cause casting defects such as pores, wrinkled skin, and slag inclusions