Quality Control

Below is Neodymium magnet process flow.

In the total process flow,we have 4 quality control point:
1)after sintering, use BH test instrument, test Br, Hcj,Hcb,BH(max)
verify raw material if meet grade requirement or not
2)after machining, use micrometer , test size(length,width,thicknes,diameter)
pick out smaller or larger ones
3)before magnetised, check magnet surface coating quality
4)after magnetised, check magnet appearance,pick out broken ones

when pick out un-qualified ones,different precessing mode in above 4 QC step: