The structure, phase composition, and residual stresses of diffusion boride layers formed by thermal-chemical treatment on the die steel surface

OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 23 No. 2 2021 Fig. 12. Diagram of residual stresses in the sample after boriding at 1050 °C Conclusion Thus, boriding at 950 °C is more preferable than boriding at 1050 °C in terms of compressive RS. Nev - ertheless, significant fluctuations of the RS in the diffusion layer and in the adjacent (transitional) zone may negatively affect the operational properties. Despite the tensile stress on the surface of the diffusion layer after high-temperature TCT, the RS distribution is smoother compared to low-temperature boriding. In ad- dition, the diffusion layer has a greater thickness (up to 100 μm) after high-temperature TCT. It is recom - mended to apply subsequent finishing treatment (fine grinding) to ensure the performance properties of the surface in a broader range of use (dimensional accuracy, roughness, level and RS sign). References 1. Voroshnin L.G., Mendeleeva O.L., Smetkin V.A. Teoriya i tekhnologiya khimiko-termicheskoi obrabotki [Theory and technology of chemical and heat treatment]. Moscow, Novoe znanie Publ., 2010. 304 p. ISBN 978-5- 94735-149-1. 2. Krukovich M.G., Prusakov B.A., Sizov I.G. Plasticity of boronized layers. Springer Series in Materials Science , 2016, vol. 237, pp. 111–227. DOI: 10.1007/978-3-319-40012-9. 3. Kulka M. Trends in thermochemical techniques of boriding. Kulka M. Current trends in boriding: Techniques . Cham, Switzerland, Springer, 2019, pp. 17–98. DOI: 10.1007/978-3-030-06782-3_4. 4. Bel’skii E.I., Sitkevich M.V., Ponkratin E.I., Stefanovich V.A. Khimiko-termicheskaya obrabotka instrumental’nykh materialov [Chemical and thermal treatment of tool materials]. Minsk, Nauka i tekhnika Publ., 1986. 247 p. 5. Burkin S.I., Shimov G.V., Andryukova E.A. Metallurgiya. Ostatochnye napryazheniya v metalloproduktsii [Metallurgy. Residual stresses in metal products]. Moscow, Ekaterinburg, Yurait Publ., 2018. 247 p. ISBN 978-5- 534-06500-8. 6. Pishchov M.N., Bel’skii S.E. Analiz ostatochnykh napryazhenii v uprochnennom sloe zubchatykh koles trelevochnogo traktora posle provedeniya khimiko-termicheskoi obrabotki [Analysis of residual stresses in the hardened layer of skidder gear wheels after chemical and thermal treatment]. Trudy BGTU. Seriya 2, Lesnaya i derevoobrabatyvayushchaya promyshlennost’ = Proceedings of BSTU. Series 2, Forest and Woodworking Industry , 2010, iss. 18, pp. 294–298. 7. Pavlov V.F., Vakuljuk V.S., Afanasieva O.S., Bukatyi A.S. Otsenka vliyaniya khimiko-termicheskoi obrabotki na soprotivlenie ustalosti obraztsov pri normal’noi i povyshennoi temperaturakh [Evaluation of thermochemical treatment influence on fatigue strength of specimens under normal and high temperatures]. Vestnik Samarskogo gosudarstvennogo aerokosmicheskogo universiteta = Vestnik of Samara State Aerospace University , 2012, no. 5 (36), pp. 113–119.