SÍS Jiří SVÚM a.s.

Different Diffusion Behavior of Alloy Elements as a Consequence of Mistaken Material and Usual Heat Treatment

Co-authors MIKULOVÁ Dagmar

Material mistaken is very frequent reason for premature failure in industry. It could be also very interesting source of informations from theoretical point of view. One of these cases were investigated in this work. It was used X5CrNiCuNb17-4-4 stainless steel for production of bolts. The material was heat treated by common way for bolts using carbonitriding. The surface layer with some interesting properties is a result of this procedure. The hardness in this layer slightly increases with growing distance from surface which is absolutely opposite in comparison with theory. The content of nitrogen in this layer is parctically zero but on the border between the layer and basic material is a line where content of nitrogen is 1,4wt.%. The diffusion processes during carbonitriding could be used as a explanation of these results.