Is it possible to replace destructive testing with measurements performed by the 3MA system (Micromagnetic Multiparameter Microstructure and stress Analysis) to assess nitriding layer depths - combination and diffusion - on parts? To answer this question, the Component NDT working group at Cetim (Centre technique des industries mécaniques) has launched a study to evaluate this non-destructive testing (NDT) process, which combines several electromagnetic measurements in a single probe, in this type of application. Measurement quality under the microscope
On a set of parts of simple geometry treated by different nitriding processes - liquid, gaseous, ionic, carbonitriding - three characteristics were monitored: the thickness of the diffusion layer, the thickness of the combination layer and the compactness of the porous layer in the combination layer. For each case studied, the quality of the 3MA estimates was assessed.
The experts' conclusion: provided you don't neglect device calibration, this technology delivers encouraging results, as revealed in the book entitled "3MA nitriding depth measurements available on Cetim's website, under " Mecatheque ".