Nova  Data Testing  Labs

BASIC PRINCIPLES OF Liquid Dye Penetrant  Inspection

Dye Penetrant Testing (PT) is used to inspect materials that are non-ferrous (non-magnetic). This inspection utilizes penetrating dyes and capillary attraction to expose surface defects on stainless steel, aluminum, titanium, brass, plastic, glass and any other non-magnetic material.

A liquid dye is applied to the surface of the part and allowed time to seep into the surface breaking defects. The excess liquid is then removed from the surface of the part. The final step in the process is the visual inspection. A "blotter" (dry powdered) material is applied which will draw out the dye which has seeped into a crack and cause it to be visible to the naked eye.