Increased durability of power engineering parts to method of carbonitriding on the macrodispersed mixture

• Дата: 2014
• Автор: Костик, Катерина
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: Інститут енергетичних машин і систем ім. А. М. Підгорного Національної академії наук України 2014
• Теми: carbonitriding; steel; diffusion layer depth; surface microhardness; diffusion; УДК 621.785.53
• Онлайн доступ: https://journals.uran.ua/jme/article/view/19924
• Назва журналу: Energy Technologies & Resource Saving

The purpose of the paper was to study the influence of technological parameters of carbonitriding in macrodispersed powder on the properties of structural steel 40X. The problem was solved by finding the optimum temperature and time of treatment. For the estimation of the parameters, typical for the diffusion layers, the study of the influence of carbonitriding time and temperature on the depth and hardness of the hardened layer was used. Based on the studies, the optimal temperature of 40X steel carbonitriding, corresponding to550°C, which provides the greatest thickness of the diffusion layer (0.5 mm) at a high surface hardness (800 MPa) was selected and justified. The analysis of experimental data showed that the best ratio of surface hardness and depth of the carbonitrided layer is achieved by the exposure for 5 hours. The coefficients of nitrogen diffusion in steel for the proposed saturation method were calculated. The new method of low-temperature carbonitriding, allowing to carry out the treatment in the box furnace just in 5 hours with obtaining of sufficient diffusion layers was pro-posed. The practical significance of this paper lies in the fact that the application of the proposed carbonitriding method allows significant reduction of the thermochemical treatment duration.