Aspects of Nitrated Layer Structure for Some Types of Austenite Stainless Steel
Abstract
The analysis of nitrated layer diffractograms and the structure marked out the presence of complex nitrides combinations layer for all types of steel except for code 6 steel type 2CuMoNiCr200 which because of the very high index of austenite stability, 29.9, presented a layer made of nitrogen solid connate solution in austenite. In the case of stainless austenite steel types nitrogen diffusion and, consequently nitrated layer formation depends on the concentration of alloying elements in steel, on austenite stability indices. Code 2 and code 3 steel types that have the smallest stability indices have the thickest layer and are followed by code 3 and code 4 steel types. On the fifth place is code 1 steel type which has a thinner layer, approx. 21 jam and on the last place there is code 6 steel type that, as it was shown, does not form a nitrides layer.
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