Influence of surface integrity after turning on the consecutive plasma nitridation and barkhausen noise emission

This paper deals with non destructive evaluation of components after plasma nitridation via Barkhausen noise techniques. The effect of the different surface state before plasma nitriding is studied via non destructive Barkhausen noise technique as well as the conventional destructive techniques. Turning operation was performed by the use of the inserts of variable flank wear. The results of experiments show that Barkhausen noise emission is a function of tool flank as well as the different regime of heat treatment. The different state of the surface before plasma nitriding results into the different thickness of compound layer. Furthermore, also the underlying diffusion layer state differs.