A ceramic capacitor is one of the widely used electronic components and has brought great convenience to our daily life. On the basis of the information searched by Easybom, the ceramic capacitor may come into failure modes when in use. Easybom has analyzed the failure modes and explain the reasons why they occur respectively according to information searched by them in order to help you avoid these failure modes.
The main failure mechanism causing the breakdown of ceramic capacitors
- The dielectric material has defects, or contains conductive impurities or conductive particles;
- The electrical aging and thermal aging of the dielectric;
- The electrochemical reaction inside the dielectric;
- Silver ion migration;
- The dielectric is mechanically damaged during the capacitor manufacturing process;
- The molecular structure of the dielectric changes;
- Arcing between poles in high humidity or low pressure environment;
- The dielectric is short-circuited instantaneously under the action of mechanical stress.
The main failure mechanism causing the circuit of ceramic capacitors open
- “Self-healing” occurs in the lead part, so the electrode and the lead wire are insulated;
- The contact surface of the lead wire and the electrode is oxidized, causing a low-level open circuit;
- The lead wire is poorly contacted with the electrode;
- The anode lead foil of the electrolytic capacitor is corroded and fractured;
- The electrolyte of the liquid workbench is dry or frozen;
- The dielectric instantaneously opens under the action of mechanical stress.
The main failure mechanism causing the deterioration of the electrical parameters of ceramic capacitors
- Moisture or surface pollution;
- Silver ion migration;
- Self-healing effect;
- Electrical aging and thermal aging of the dielectric;
- The working electrolyte volatilizes and thickens;
- Electrode corrosion;
- Electrode corrosion in wet electrolytic capacitor;
- The role of impurities and harmful ions;
- The contact resistance between the lead wire and the electrode increases.
The main reasons causing leakage of ceramic capacitors
- Under the action of electric field, the impregnating material is liberated to improve the air pressure in the shell;
- The metal shell of the capacitor and its sealing cover are not well welded;
- The insulator is poorly welded to the shell or lead wire;
- The mechanical seal of the semi-sealed capacitor is poor;
- The surface of semi-sealed capacitor leads is not smooth enough;
- The working electrolyte corrodes the solder joints.
The main cause of corrosion or breakage of ceramic capacitors
- Electrochemical corrosion occurs under the action of electric field in high temperature environment;
- The electrolyte leaks along the lead wire, causing the lead wire suffer chemical corrosion;
- The lead wire is mechanically damaged during the manufacturing process of the capacitor;
- The mechanical strength of the lead wire is insufficient.
The main cause of the rupture of ceramic capacitor insulator
- Mechanical damage;
- The remaining heat in the sintering process of the glass powder insulator is too large;
- The welding temperature is too high or uneven.
The main cause of arcing on the surface of the insulators
- The surface of insulator is wet, reducing the surface insulation resistance;
- The design of insulator is unreasonable;
- Improper selection of insulator;
- The air pressure is too low.
Having a full understanding of the cause of the failure modes given by Easybom, you can completely avoid them when in use, thus smoothing the working process.