How to choose the right potting compound, mainly consider these three points:
1. The performance requirements after potting, such as the use of temperature, hot and cold alternating conditions, components to withstand the internal stress situation, outdoor or indoor use, whether the requirements of flame retardant and thermal conductivity and color.
2. Potting process: manual/automatic, room temperature/heating, complete curing time, solidification time of the glue after mixing.
3. Potting cost: the specific gravity of the potting material varies greatly, you need to look at the actual cost of the potting, rather than simply look at the price of the material.
Epoxy resin potting compound is mostly hard, very few are slightly soft. This type of material has an advantage: good adhesion to the material, high hardness after curing, good acid and alkali resistance. In general, epoxy resin temperature resistance of 100 ℃, its light transmission is good, can be used as a transparent material.
Applications: Generally used for the potting of non-precision electronic devices such as LEDs, transformers, regulators, industrial electronics, relays, controllers, power supply modules and so on.
Polyurethane potting compound is slightly soft after curing, the bonding force is between epoxy resin and silicone. Good low temperature resistance, can make the installation and debugging of electronic components and circuits are not affected by vibration, corrosion, humidity and dust, etc., excellent electrical insulation.
Application scope: generally used in the potting of electronic components that do not generate much heat, such as transformers, converters, capacitors, inductors, varistors, linear engines, circuit boards, LEDs and so on.
Silicone potting compound includes one-component silicone potting compound and two-component silicone potting compound. Cured material is soft, can form a soft elastomer protective layer, resistance to mechanical shock and thermal shock to components; stable physical and chemical properties, good resistance to high and low temperatures, can be in the -40 ~ 200 ℃ temperature in the long-term work; excellent weathering, outdoor use for more than 10 years can still play a good role in protecting, and not easy to yellowing; electrical performance, insulation performance is excellent, potting can effectively improve internal Excellent electrical properties, insulation properties, potting can effectively improve the insulation between the internal components and lines, to protect the components used in high-voltage environment; after the coating can flow/fill/self-leveling, easy to discharge bubbles; can be returned to repair, can be sealed after the components out of the repair and replacement.
Application scope: suitable for potting a variety of harsh environments and high-end precision/sensitive electronic devices. Such as: LED, photovoltaic materials, diodes, semiconductor devices, sensors, car computer ECU, etc., to play the role of insulation, waterproof, moisture-proof, dustproof, shock absorption.
