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Information × Registration Number 0205U006677, 0104U003420 , R & D reports Title The effect of non-equilibrium stress state of near-surface region on phase transformations and properties of iron alloys under nitriding. popup.stage_title Head Sydorenko Sergij Ivanovych, Доктор фізико-математичних наук Registration Date 13-12-2005 Organization National Technscal University of Ukraine "Kiev Polytechnic Institute". popup.description2 Research object - iron, alloys of iron with a nickel (0,5 and 5 the masses. %) and iron with a chrome (1,0 and 1,5 the masses. %). Purpose of work - creation of physical bases of processes of phase transformations and strengthening of the alloys of iron at diffusion saturation by nitrogen of non-equilibrium stress state created by means preliminary plastic deformation (PPD). Research methods - metallography, microhardness, X-ray diffractometry, electron microscopy and Messbaouer spectroscopy. Researches showed that creation of non-equilibrium stress state by plastic deformation of iron and iron alloys before nitriding substantially accelerated the process of saturation, affecting kinetics of formation of phases, eventual structure, microhardness, phase and chemical composition of diffusive layers. Acceleration of diffusive processes can be related to influencing of mobile regional dislocations which are able to transfer the atmospheres of admixture atoms of penetration after a dynamic dislocation mechanism. Definite narrow ranges of preliminary deformations, in which at next nitriding there is forming of layers of nitrides e - and g' -phases maximal thickness and substantial (approximately in 2 times) rise of microhardness of superficial diffusive layer, and also slowness of layer. Product Description popup.authors popup.nrat_date 2020-04-02 Close