Influence of strain hardening on gaseous nitriding of steels
TypeCommunications avec actes
Machining is known to introduce plastic straining and residual stress gradients in surface of mechanical parts. If not controlled, the mechanical state of a surface can influence adsorption and diffusion of atoms during subsequent chemical surface treatments, such as nitriding. In the present work, the influence of strain hardening on gaseous nitriding of steels is studied. The nitriding process was carried out using a laboratory set-up enabling the control of nitriding parameters (time, temperature, nitriding potential) on 33CrMoV12-9 steel samples. Homogeneously strain hardened samples are obtained by controlled tensile tests, enabling to nitride samples at different levels of strengthening. Results are compared to a reference state, obtained from tensile specimen not submitted to strain-hardening, as well as an industrially representative sample nitrided using the same conditions. Nitrided samples are characterized by SEM observations, hardness measurements and carbon and nitrogen in-depth concentration profiles.
Files in this item
Showing items related by title, author, creator and subject.
JÉGOU, Sébastien; GUILLOT, Benjamin; BARRALLIER, Laurent (2016)Gaseous nitriding is a well-established thermochemical treatment of carbon iron-based alloys that considerably enhances corrosion, wear and fatigue resistances of critical mechanical parts such as crank shafts and bearings. ...
Degradation of gaseous nitriding of steel by lubricant contamination — Effect of in-situ pre-treatments GUILLOT, B.; JEGOU, Sébastien; BARRALLIER, Laurent (Elsevier, 2017)The present work focuses on the industrial inhibition of gaseous nitrided parts and on the industrial in-situ pre-treatment that can be used to avoid these inhibitions. The first objective is to obtain a repeatable defective ...
Determination of residual stress in nitrided steels with transmission angle-dispersive diffraction JEGOU, Sébastien; BARRALLIER, Laurent (2014)Residual stress analysis with transmission angle-dispersive diffraction is carried out on nitrided steels. It aims evaluating residual stresses within the ferritic matrix but also within secondary phases such as nano-scale ...
JEGOU, Sébastien; BARRALLIER, Laurent; KUBLER, Régis; SOMERS, Marcel (Hanser, 2011)Development and evolution of compressive residual stress during nitriding treatment are studied. A model carbon iron-based alloy Fe-3wt.%Cr-0.35wt.%C was nitrided in gas at 550 °C for different times. Microstructural ...
JEGOU, Sébastien; KUBLER, Régis; BARRALLIER, Laurent; ROCH, François (2009)Nitriding of steels is an important treatment in duplex hardening methods. This treatment is known in the art but some advances still need to be done in terms of residual stress understanding. Although residual stresses ...