The problem of bubbles in silicone encapsulant products is a common phenomenon in products in this industry. To prevent the occurrence of bubbles, it is necessary to formulate an effective and controllable inspection standard method. Today, I will share with you how to check whether the bubbles are completely eliminated after the silicone potting sealant is completely cured.
colloidal surface
After the silicone encapsulant is completely cured, if there are air bubbles on the surface of the colloid, the general manifestations are bubbling, pits, and pitting. As long as it is in a strong light environment, it can be easily detected. If there are bubbles on the surface that have not been eliminated, such a situation will lead to a decrease in the protective properties of the silicone potting compound, such as moisture resistance and water resistance, especially in an environment with high moisture and a shorter service life. At the same time, surface bubbles exist. Prolonged, environmental alternating impact, the colloid may crack in advance, leading to a series of application problems.
Inside the colloid
After the silicone potting compound is completely cured, there are no bubbles on the surface, does it mean that the curing is normal? In fact, the internal bubbles of the colloid are also a key factor affecting the performance. For example, the curing speed of the colloid is fast, and the surface is crusted before the internal bubbles are discharged in time, which will lead to a flat and beautiful surface, and the internal bubbles of the colloid are densely packed. Therefore, check the bubbles of the silicone potting compound. Another important point is to use a blade to cut the colloid to check and confirm that there are bubbles in the colloid, which have a great impact on physical properties and electrical properties, such as voltage resistance, voltage breakdown and so on.
solution
1. After the AB group of silicone potting glue is distributed and stirred evenly, it is recommended to use vacuum defoaming before performing the glue filling operation;
2. In order to prevent more new bubbles from being generated during the glue filling operation, especially for products with high viscosity or fast curing, the height and strength of glue filling should be controlled during glue filling;
3. Under the condition of no vacuum, choose the product with good self-discharging performance, and the colloid can be completely defoamed within the operating time.