Advantages of silica sol process High precision, good surface finish, and can cast parts with complex structures. Wide range of application materials and high quality of mold shell.

1. Silica Sol Process Introduction：

In the fields of modern machinery manufacturing, aerospace, medical equipment, hardware tools, etc., products have higher and higher requirements for the dimensional accuracy, surface finish and complex shapes of parts. Traditional casting methods have gradually become difficult to meet these high requirements, and the "silica sol process" as an advanced precision casting technology is being widely adopted with its advantages of high precision, high surface quality and strong ability to form complex structures.

So, what is the silica sol process? What are its principles and processes? What are its advantages and application value? This article will systematically introduce the whole process of this process and its importance.

2. Overview of Silica Sol Process-High-precision Technology In Precision Casting:

Silica Sol process, also known as silica sol lost wax precision casting, is a kind of investment casting technology with silica sol as a binder. It is often used in the manufacture of precision parts of metal materials such as stainless steel, carbon steel, and alloy steel.

Silica sol is a stable colloidal solution with nano-scale silica particles as the core and dispersed in water. Compared with the traditional water glass process, silica sol has higher thermal stability and better surface fineness, so it can produce higher quality castings.

3. Detailed Process Explanation-wax Is the Key:

The first step is to make a wax mold. Liquid wax is injected into the metal mold by a wax injection machine, and after cooling, a wax mold with the same shape as the final casting is formed. Usually, multiple wax molds are combined into a wax tree for batch casting.

The second step is shell making. After the wax mold is combined, the slurry and sanding are repeatedly performed, and one layer is dried each time to finally form a multi-layer ceramic shell. In this process, silica sol is used as a binder for the coating to ensure the strength and density of the mold shell. Usually 6 to 9 layers are required to achieve the desired effect.

The third step is dewaxing. Through steam or high temperature heating, the wax mold melts and flows out, leaving a hollow ceramic shell. This step is crucial and determines the accuracy of the final casting cavity.

The fourth step is to bake the mold shell. The mold shell is placed in a high-temperature furnace for baking, which can completely remove the residual wax and enhance the strength and high temperature resistance of the mold shell.

The fifth step is metal pouring. Pour molten metal, such as stainless steel, carbon steel, etc., into the mold shell at high temperature. After the molten metal fills the cavity, it cools and solidifies to form a casting of the desired shape.

The sixth step is shelling and cleaning. After the metal cools, the ceramic shell is broken and the metal casting is taken out. Then cutting, deburring, sandblasting and other treatments are carried out. Some parts also need heat treatment or machining to meet the final use standards.

4. Process Characteristics And Advantages:

The first advantage is high precision and good surface finish. The dimensional accuracy of its castings can reach CT4 to CT6. This means that many workpieces can be used directly without machining.

The second advantage is the ability to cast parts with complex structures. For example, parts with complex shapes such as internal holes, thin walls, and deep grooves can be completed with high quality by the silica sol process.

The third advantage is the wide range of applicable materials. The silica sol process is suitable for various stainless steels, carbon steels, low alloy steels, and heat-resistant steels, and has strong compatibility with materials.

Fourth, reduce processing allowances and save production costs. Since the castings are close to the finished product size, the subsequent processing volume is small, which can effectively reduce material loss and processing time.

Fifth, the mold shell has high quality. The silica sol coating is dense, has high bonding strength, and has good crack resistance, so that the mold shell maintains a stable shape during high-temperature pouring and reduces the incidence of defects.

5. Comparative Advantages With Traditional Processes:

Compared with ordinary sand casting, the silica sol process is more suitable for manufacturing small, complex structures, small batches, but high quality requirements.

Although the raw material and process costs of the silica sol process are relatively high, the high quality, high consistency, and less post-processing requirements it brings have great advantages in overall cost and efficiency.

6. Wide Range of Applications：

Silica sol precision casting is widely used in various high-precision industries, mainly including the following aspects:

First, the aerospace field. Many key parts of aircraft, such as engine parts, high-temperature structural parts, etc., are manufactured using the silica sol process to ensure their reliability and safety.

Second, the automotive manufacturing industry. Automobile engine parts, turbocharger housings, exhaust system parts, etc. have high requirements for strength and precision, and are suitable for silica sol casting.

Third, the field of pumps, valves and mechanical equipment. Pump housings, valve bodies, impellers and other parts with complex shapes and fine flow channel requirements can be formed in one step through the silica sol process.

Fourth, the medical device industry. It is used to manufacture stainless steel surgical instruments, implantable parts, etc., which not only ensures dimensional accuracy, but also meets biocompatibility requirements.

Fifth, hardware and daily necessities industry. For products with high appearance requirements such as high-end door locks, decorative parts, sports equipment, etc., the silica sol process can provide good surface effects and consistency.

7. Conclusion：

As a high-precision, high-quality advanced casting method, the silica sol process has shown strong vitality in many fields. It can not only produce complex, high-precision metal parts, but also significantly improve production efficiency and product reliability. Although the initial cost is slightly higher, from the perspective of the overall manufacturing process, finished product qualification rate, and post-processing savings, the silica sol process is undoubtedly a core technology worth investing in modern precision manufacturing.

With the continuous advancement of technology and the increase in demand for high-quality products, the application prospects of silica sol precision casting will be broader, providing solid support for the high-end development of the manufacturing industry.