Method for preparing water-based coating for sand mold casting

Abstract

The invention discloses a method for preparing a water-based coating for sand mold casting, wherein the coating is prepared from zircon powder, fused mullite powder, quartz powder, lithium based bentonite, flake graphite, silicon sol, sodium carboxymethyl cellulose, sodium alkyl benzene sulfonate, sodium sulfate, sodium carbonate, n-caprylic alcohol, fatty alcohol-polyoxyethylene ether and water;and the preparation method comprises the following steps: 1) firstly, uniformly mixing the zircon powder, the fused mullite powder and the quartz powder aggregates with a proper amount of water in anattrition mill so as to obtain a base material; 2) sequentially adding the silicon sol, the sodium carboxymethyl cellulose, the sodium alkyl benzene sulfonate, the sodium sulfate, the sodium carbonate, the n-caprylic alcohol and the fatty alcohol-polyoxyethylene ether into the wet base material which is mixed, then adding a proper amount of water into the obtained mixture; and 3) adding the rest of water into the attrition mill, uniformly stirring and grinding.

Description

technical field [0001] The invention relates to the field of casting, in particular to the field of sand casting. Background technique [0002] When using sand molds to produce castings, it is a very important process to apply casting coatings on the working surface of the mold (core). Casting coating is a kind of refractory coating, and its main components are: refractory powder, carrier liquid, suspending agent, binder and other additives. The main function of the coating is: to block the direct contact between the molten metal and the surface of the sand mold (core), and play an isolation role, eliminating the necessary elements for the physical or chemical reaction between the molten metal and the surface of the sand mold (core), thereby effectively preventing and Reduce defects such as sand sticking, sand inclusions, and sand holes on the surface of castings; improve the surface strength of the mold (core); control the cooling rate of castings to prevent shrinkage cavi...

AI Technical Summary

Problems solved by technology

[0005] Chinese patent literature discloses a kind of name is " alcohol-based or water-based sand powder anti-penetration sticky sand foundry coating " (publication number: CN1666828, publication date: September 14th, 2005), its raw material composition is complex and diverse, batching, preparation The procedures are complicated, the manufacturing cost is obviously high, and its technical performance indicators still cannot meet the requirements, mainly reflected in: 1. The performance of the brushing process is not good; 2. The storage and stability of the paint are poor, and the viscosity is easy to appear during storage. decline