The above introduced to you the internal factors of ceramic capacitor failure, and today I will talk to you about the external factors of failure.
01 Thermal crack
It is mainly caused by the temperature shock of the device during soldering, especially wave soldering, and improper rework is also an important cause of temperature shock cracks.
02 Mechanical Stress Crack (Flex Crack).
Multilayer ceramic capacitors are characterized by their ability to withstand large compressive stresses, but their ability to resist bending is poor. Any operation that may cause bending and deformation during device assembly can cause the device to crack. Common stress sources are: chip alignment, circuit board operation during the process;Factors such as people, equipment, gravity and other factors in the process of circulation;Through-hole component insertion;Circuit testing, single board splitting;Circuit board mounting;Circuit board positioning riveting;Screw mounting, etc. This type of crack generally originates at the metallized ends of the upper and lower parts of the device and propagates along the 45-angle direction inside the device. This type of defect is also the type of defect that actually occurs the most.
Ceramic capacitors are the most commonly used capacitors in electronic devices, with an annual production of about one megabyte. Ceramic capacitors are capacitors that use ceramics as the dielectric medium. The structure consists of two or more alternating ceramic and metal layers, which are connected to the electrodes of the capacitor.