What is the size shrinkage rate of liquid silicone encapsulated products?
Liquid silicone encapsulated products play a crucial role in modern industrial manufacturing, and their excellent physical and chemical properties make them the preferred material in many industries. However, for liquid silicone encapsulated products, a key parameter indicator is their size shrinkage rate. The size shrinkage rate not only directly affects the dimensional accuracy and appearance quality of the product, but also affects the performance and service life of the product.
1、 Overview of Liquid Silicone Coating Products
Liquid silicone encapsulation is a technology that uses liquid silicone material to wrap objects that need protection through specific technological means. This technology is widely used in fields such as electronics, healthcare, automotive, and aviation, providing a soft and durable protective layer for various complex shaped products. Liquid silicone encapsulated products have excellent heat resistance, cold resistance, corrosion resistance, electrical insulation, and good biocompatibility, which can meet the high requirements of different industries for material performance.
2、 Definition and influencing factors of size shrinkage rate
Size shrinkage rate refers to the rate of size change caused by chemical reactions and physical changes during the curing process of liquid silicone encapsulated products. In general, the size shrinkage rate of liquid silicone encapsulated products is influenced by various factors, such as the type of silicone material, curing conditions, mold design, product shape and size, etc. Therefore, to accurately grasp the size shrinkage rate of liquid silicone encapsulated products, it is necessary to conduct in-depth analysis of these influencing factors.
3、 Measurement method for dimensional shrinkage of liquid silicone encapsulated products
The size shrinkage rate of liquid silicone encapsulated products is usually measured using the following methods:
1. Mold method: By designing a specific mold, liquid silicone is injected into the mold. After the silicone is cured, the product size is measured and compared with the mold size to calculate the size shrinkage rate. This method is simple and easy to implement, but it is greatly affected by mold accuracy and measurement errors.
2. Direct measurement method: Directly measure the size of liquid silicone coated products on the product production line, compare it with the product design size, and calculate the size shrinkage rate. This method can reflect the size changes of the product in real time, but it is greatly affected by the production environment and equipment accuracy.
3. Numerical simulation method: Use finite element analysis software to numerically simulate the curing process of liquid silicone encapsulated products and predict the size shrinkage rate of the products. This method can accurately predict the size changes of products, but requires high computational resources and professional knowledge.
4、 Control strategy for size shrinkage of liquid silicone encapsulated products
In order to reduce the size shrinkage rate of liquid silicone encapsulated products, improve the dimensional accuracy and appearance quality of products, the following control strategies can be adopted:
1. Choose appropriate silicone material: Select silicone material with lower shrinkage rate according to the product’s usage environment and performance requirements.
2. Optimize curing conditions: By adjusting parameters such as curing temperature, time, and pressure, control the curing process of silicone and reduce size shrinkage.
3. Improve mold design: Optimize mold structure, improve mold accuracy, and reduce the impact of molds on product dimensions.
4. Strictly control the production environment: maintain the stability and consistency of the production environment, and reduce the impact of external factors on product dimensions.
5. Strengthen quality control: Establish a sound quality management system and strictly inspect and control the size of liquid silicone encapsulated products.
5、 Application examples of size shrinkage rate of liquid silicone encapsulated products
In practical applications, the size shrinkage rate of liquid silicone encapsulated products has a significant impact on the performance and service life of the products. Taking electronic products as an example, excessive size shrinkage of liquid silicone encapsulated products can lead to loosening and misalignment of internal components, thereby affecting the electrical performance and reliability of the product. Therefore, in the manufacturing process of electronic products, it is necessary to strictly control the size shrinkage rate of liquid silicone encapsulated products to ensure product quality and stability.
Generally speaking, the typical shrinkage rate of liquid silicone is:
Vertical (flow direction) is approximately 5% to 8%
Horizontal (perpendicular to the direction of flow) is approximately 10% to 15%
Please note that these values are approximate range values and may vary depending on specific applications, process conditions, and types of silicone rubber. In order to obtain accurate data, sample testing should be conducted before production to determine the exact shrinkage rate under specific conditions.
