Why is the Silica Sol Casting Process So Expensive?

Many of my friends have asked me this question: Why is silica sol casting so expensive? Here, I will explain the core value of silica sol casting.

First of all, as a buyer, you need to understand what casting is. Casting involves melting metal, creating a mold, and pouring the molten metal into the mold. After solidification, there is a method to form metal parts with a certain shape, size, and performance. There are three main casting methods: sand casting, permanent mold casting, and investment casting (lost-wax casting).

Since our silica sol process is a type of investment casting, we will focus on the investment casting method.Investment casting simply involves making a wax replica of the object to be cast, then dipping this wax replica into a tank containing sand/powder and allowing it to dry, so that the wax replica is covered with a layer of sand mold. These steps are repeated until the outer mold is thick enough to withstand the casting process. Next, the wax in the mold is melted and drained out. After that, the mold needs to be heated multiple times to increase its hardness before it can be used for casting. This method offers excellent precision; however, the cost is quite high because the sand/powder is expensive, and the production process requires multiple heating steps and is relatively complex.

The surface roughness of products cast using the silica sol process can reach Ra3.2-6.3. Since the cast blank is almost in its final shape, this achieves the goal of avoiding machining or requiring only minimal machining, which reduces costs to a certain extent and shortens production time.

There is another more commonly used investment casting method that utilizes the water glass process. Compared with castings produced by the silica sol process, water glass casting has certain advantages in terms of price, meaning it is more economical. The above is a brief analysis of the differences between the two processes during production.

Differences in the production process lead to significant differences in the final products. Compared with products produced by the water glass process, those made by the silica sol process have higher dimensional accuracy and better surface roughness. If you prioritize quality, please respect its price; if you want a more affordable product, please accept its shortcomings! What you get depends on how much you are willing to pay for it.

Finally, here is a summary of the core advantages of silica sol casting: excellent casting surface quality and high dimensional accuracy, which saves a great deal of time in surface treatment and external processing for dimensional adjustments. From the perspective of the finished product, it actually reduces costs in the long run.

The above are products made by the water glass process.

The above are products made by the silica sol process.