Silica Sol Investment Casting

The silica sol also shares the name of water glass in general, it is used by
the meatal casting process as mold adhesive which is mixed with sand and
several other materials. The silica sol is applied to both sand casting and
investment casting technics. It is one of the most common investment casting
processes. As the molding material, silica sol is able to stand temperature up
to 1800℃. Similar to other investment casting processes, the silica sol
investment casting process mainly consisted of wax injection, assembly, shell
preparation, dewax, pouring, cut-off, and finished casting, etc.

Compared to the resin investment casting, the silica sol method dewaxes into
the high-temperature water, and the ceramic mold is made of water glass quartz
sand. The surface quality is not as good as the resin casting, but it's cheaper
and a bigger-sized part could be manufactured than silica sol casting.

Application of Silica Sol Casting
Mainly the silica sol is applying to the precision casting, because of its
relatively high production cost but gives out a very fine accurate dimension,
nice surface finish, and very good quality result overall. One of the other
advantages for silica sol is that the internal defects such as porosity, holes,
shrinkage are better controlled compared to another way of casting. So when you
looking for a method to produce a small part but with high accuracy, surface
demand, high corrosion resistance and you don't want to waste time waiting for
the casting quality in slow improved gradually, silica sol investment casting
is surely on your options list.

The Basic Property of the Product Made by Silica Sol Casting:

dimension tolerance ±0.1mm, CT4~6；

surface finish Ra6.3;

wall thickness up to 1mm;

unit weight extent 0.1~100kg;

unit size limitation 0.01~0.5 meter;

degree of complexity- very complex;

machining required- less or none due to its accurate dimension;

production lead time- long;

production cost- high;

Influence Factor in Silica Sol Investment Casting

The whole casting process has more than 40 procedures, the process is complex,
and there are many process factors that affect the casting quality.

There are many kinds of raw and auxiliary materials, such as silica sol, wax,
zircon sand, molybdenum powder, defoamer, wetting agent, steel, rare metal,
etc. According to the different mesh, there are more than 10 kinds of sols,
including precision casting surface silica sol, precision casting backside
silica sol, ordinary silica sol, enhanced silica sol, fast-drying silica sol,
and zirconia powder. It is not suitable to control its quality, which affects
the casting quality in different degrees.
The production cycle is long and there are many uncontrollable factors. In the
whole process, only the shell-making process takes 3-5 days. It takes 6-8 hours
to dry the surface shell of silica sol, 4-6 layers to dry the back shell of
silica sol, and 8-12 hours to dry the shell without silica sol. There are too
many uncontrollable factors and defects will be formed with slight deviations
in the process operation.

Rayforce Manufacture is a private metal casting supplier, we provide metal
casting china, vacuum die casting and etc. Want to know more? Please contact
us.

Minimum Order: 3000 metric tons

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