Tantalum capacitors do not even have a known wear out mechanism.
Ceramic capacitors over time.
The dielectric is characterized by very high nonlinear change of capacitance over the temperature range.
The capacitance value additionally depends on the voltage applied.
When using these products for time constant circuits etc please take time to fully understand their characteristics and check the actual conditions of use and actual equipment.
The terminations of ceramic capacitors will typically oxidize over time degrading solderability and affecting the wetting characteristics of the capacitor if not stored properly.
In terms of capacitor performance tantalums and ceramic capacitors differ in a few key ways.
Among ceramic capacitors the capacitance especially of capacitors classified as a high dielectric constant b x5r r x7r characteristics decreases over time.
Contact with sulfur dioxide or chlorine gas will accelerate an oxidation layer forming on the terminations.
As well they have very high losses and age over time.
Ceramic capacitor aging class ii dielectrics experience a phenomenon called aging and it is simply a decrease in capacitance over time due to crystallinechanges that occur in all class i i dielectrics x7r x5r and y5v.
When it comes to capacitors a logarithmic decrease in capacitance over time is referred to as aging.
This is caused by the relaxation or realignment of the electrical dipoles within the capacitor.