Surface Hardening by Nitration for Some Stainless Austenite Steel Types
Journal Title: Analele Universitatii "Dunarea de Jos" din Galati. Fascicula IX, Metalurgie si Stiinta Materialelor - Year 2006, Vol 29, Issue 1
Abstract
Stainless austenite steel types have a good resistance to corrosion in different natural, industrial environments but their hardness and mechanical resistance are low enough. In order to assure an increased resistance to abrasion it is necessary to increase also the surface hardness. This thing is possible if the nitrogen concentration in the surface layer is increased by means of nitration. The researches made on stainless austenite steel types pointed out a strong hardening tendency for the major part of steel types except for steel type 2CuMoNiCr200. The austenite in this has a very high degree of stability as a result of high content of alloying elements. When the nitrogen is diluted, the hardness is more reduced. Hardness strong increase in the other steel types is determined by complex nitrides separations favoured by nitrogen diffusion and increase of its concentration in the surface layer. The thickness of the hard layer increases depending on the period of nitration process from one hour to 3 hours and is influenced also by the characteristics of each sample.
Authors and Affiliations
Ovidiu DIMA, Nelu CAZACU
Mass Erosion and Material Transfer at the Deposition of Layers by Inverse Electroerosion
The deposition and alloying of the superficial layers by inverse electroerosion or by electric spark given by a vibrating electrode permits to obtain a large scale of properties at the surface of metallic materials from...
Electrical Properties of Ultra-Sonicated Epoxy Resin
As ultra-sonication is a mostly used method to disperse the particles into the polymer matrix, the aim of this study is to point out the effect of epoxy’s exposure to ultra-sounds over the electrical properties, especial...
Contributions in the Domain of the Contact Stresses Between Cylinders of Cold Rolling
Elasto-plastic contact stresses between working cylinder and support cylinder of cold rolling using FEM are presented in this paper. Pressure and tractions resulted from the rolling process were obtained by using a calcu...
The Consequences of Heavy Metals Impact on Primary Teeth
Since the metals deposited in the teeth during formation and mineralization processes are to a large extent retained, human teeth receive a considerable attention as indicators of heavy metal exposure. The objective of t...
Microstructural Evolution of Al 1100 Aluminum Subjected to Severe Plastic Deformation
The goal of this document is to promote a sequence of bulk-deformation processes able to produce ultrafine grain and also nanostructured wires with adequate length to be interesting for processing in metallurgical indust...