These materials are basic non-organic chemicals and should be stable with time. Shock can cause cracks which form air gaps. High temperatures can change the mu.
These materials are basic non-organic chemicals and should be stable with time. Shock can cause cracks which form air gaps. High temperatures can change the mu.
some matterial like ferrite that settele on magnetizing enviroment will degraded over time but with low degaraded only making it,s characteristics diffrent as it for firs time (it's olso depent on material of te ferryte)