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.
Downloads
References
[2]. Cheşa I. s a Alegerea şi utilizarea oţelurilor Ed. Tehnică Buc., 1984.
[3]. Dumitrescu T. Tratamente termochimice Ed. Universităţii din Galaţi, 1980.
[4]. Dobrovici S. Cercetări privind tehnologia carbonitrurării în strat fluidizat aplicată oţelurilor. Teză de doctorat Galaţi, 1999.
[5]. Truşculescu M. Oţeluri inoxidabile şi refractare. Ed. FACLA Timişoara, 1983.
[6]. Berns H. Case hardening of stainless steel using nitrogen. Ruhr University, Bochum, Germany, 2002.
[7]. Berns H. Solution nitriding of stainless steel for process engineering, Mat.-wisws. u. Werkstofftech. 31/2000.
[8]. Mocanu D. R. Încercarea materialelor. Ed.Tehnică Buc., 1982.
[9]. Vellier M. Solution apportees aux problemes de la corosionabrasion par certaines aciers inoxydables austenitiques et austenito-feritiques. Conference internationale des arts chimiques Paris, 1976.
[10]. Dima O. Mitoşeriu O. Levcovici S. Studiu asupra aspectelor de coroziune evidenţiate pe table şi îmbinări sudate din instalaţiile de fabricaţie a celulozei chimice prin procedeul sulfit din cadrul combinatelor CCH Zărneşti, CCH Letea Bacău, CCH Brăila. Tehnologii Calitate Maşini şi Utilaje 36 Ed. Tehnică Buc.1999. Lucrările simpozionului Ecologie. Acoperiri metalice. Braşov, 1999.
[11]. Dima O. Surface hardening by nitration for some stainless austenite stainless steel type. Galati, 2006.