Varistors, with their nonlinear voltage-current characteristics, are widely used in various electronic devices primarily to protect circuits from transient voltage surges. When a circuit experiences a surge voltage, varistors respond quickly by lowering their resistance, providing a discharge path for current, and clamping the voltage to protect downstream circuits from damage.
Varistors are typically installed in electronic devices exposed to harsh environments such as high temperatures, humidity, and corrosive conditions. In high temperatures, varistor internal structure may change, leading to performance degradation; in humid environments, moisture can penetrate inside causing short circuits or corrosion; and in corrosive environments, the varistor surface may corrode, resulting in failure.
To ensure stable operation in diverse environments, varistors require surface coating. The choice of coating material directly impacts varistor stability and longevity.
Epoxy resin, a thermosetting resin, exhibits excellent physical, chemical, and electrical properties. Upon reaction with a curing agent, it forms a highly cross-linked three-dimensional network structure, offering high hardness, wear resistance, corrosion resistance, and excellent insulation properties. This makes it suitable as a surface coating material for varistors.
The protective layer formed by epoxy resin effectively isolates varistors from corrosive substances like moisture and oxygen in the external environment, preventing damage.
Cured epoxy resin provides outstanding mechanical strength and thermal stability, capable of withstanding mechanical stress and temperature variations without cracking or deformation, thereby ensuring varistors maintain stable performance in harsh environments.
Its high electrical insulation properties prevent issues such as current leakage and arc discharge, significantly enhancing the reliability and stability of varistors.
Choosing epoxy resin as the surface coating material for varistors thus ensures robust protection for the stable operation of electronic devices.
Dongguan Zhixu Electronics (also JYH HSU, short for JEC) offers a comprehensive range of electronic component models with guaranteed quality and reliable after-sales support. Our products are certified under the ISO9001:2015 quality management system. Welcome to contact us for cooperation.
Post time: Mar-05-2025