YDK quick drying series silica sol

Product Parameters

Product Features

Quick drying silica sol is a process of polymer modification on the surface of silica sol to establish wet strength of casting shell molds in advance, shorten the drying time of casting shell molds, and thus improve casting production efficiency.

Because water is used as the solvent in silica sol, the drying and hardening time of silica sol shell is not only related to the degree of stability damage, but also to the rate of water loss. Therefore, the gel hardening mechanism of fast drying silica sol shell is as follows:

First of all, when preparing the slurry, quartz powder or mullite powder will impact and destroy the spatial network structure of polymer molecules, polymer molecules will break away from the adsorption of particles, the adsorption layer of fast drying silica sol will be destroyed, and the particles will collide to generate gel and water with strong cohesiveness. That is:

MSiO2 · nH2O → mSiO2 · (n-1) H2O+H2O

Secondly, the polymer molecules that have detached from adsorption are reconnected to form a thin polymer film with adhesive properties. In addition, by controlling the environmental humidity and wind speed, both the quick drying silica sol shell and the silica sol shell form a high inside and low outside humidity gradient, accelerating the evaporation of water and shortening the gelation hardening time.

The usage conditions of quick drying silica sol:

1. This product does not require any changes to the shell making process during use, and the requirements for the selection of precision casting powder, coating ratio, and environmental conditions such as temperature and humidity in the shell making workshop are similar to those of ordinary silica sol.

2. Under the same process conditions as ordinary silica sol, the interlayer drying time is about half of that of ordinary silica sol.

3. The shell has high wet strength, can withstand low humidity and high wind force, and has certain resistance to dissolution and cracking.

Product application areas

This series of products is suitable for precision castings that require high precision and fast drying speed.