##plugins.themes.bootstrap3.article.main##

In the paper the hardening process of splined semi-axles is discussed and physics of preventing the quench crack formation during intensive quenching (IQ) is explained. It is shown that during IQ process at the splined cylindrical surface very high compressive current band residual stresses are formed which prevent the possibility of quench crack formation on splines. It is enough to optimize the stress distribution through the section of semi-axle and perform IQ process in order to prevent quench cracks formation in splines. It is achieved via optimizing depth of surface hardened layer. In this case the depth of surface hardened layer for cylinders and for cylinders with splines are the same. There is no need to create a special thin shell on splines or perform carburization to create such shell. Due to larger martensite specific volume, it results in surface compressive residual stress formation. Absence of martensite phase at the core eliminates core swelling that could be a reason in tensile surface stresses. The idea is supported by FEM calculations and testing of real semi-axles in industrial condition. The new idea simplifies cardinally technological process and makes it less costly.

References

  1. Kobasko, N. I., Steel Quenching in Liquid Media Under Pressure, Naukova Dumka, Kyiv, 1980, 206 p.
     Google Scholar
  2. Kobasko, N. I., W. S. Morhuniuk, and B.K. Ushakov, Designing of Steel Intensive Quench Processes, Handbook of Metallurgical Process Design, G. Totten, K. Funatani, and Lin Xie, Eds., Marcel Dekker, New York, 2004, pp. 733–764.
     Google Scholar
  3. Kobasko, N. I., W. S. Morhuniuk, and A. P. Morganyuk, Hardening of Complex Configuration Bodies by Intensive Cooling, Proceedings of the 7th International Congress on Heat Treatment of Materials, December 11–14, 1990, Moscow, Vol. 2, 1990, pp. 232–239.
     Google Scholar
  4. N.I. Kobasko, Aronov M. A., Powell J. A., Totten G. E., “Intensive Quenching Systems: Engineering and Design”. ASTM International, USA, 2010. 234 p. doi: 10.1520/mnl64-eb
     Google Scholar
  5. Martin, H., Impinging Jets, Hemisphere Handbook of Heat Exchanger Design, G. F. Hewitt, Coordinating Ed., Hemisphere, New York, 1990, pp. 2,5. 6–1.
     Google Scholar
  6. Mikheev, M. A., and I. M. Mikheeva, Osnovy teploperedachi (Basics of heat transfer), Energy, Moscow, 1977.
     Google Scholar
  7. Kobasko, N. I., Quenching Apparatus and Method for Hardening Steel Parts, U.S. Patent No. 6,364,974 BI, April 2, 2002.
     Google Scholar
  8. Kobasko, N. Optimal hardenability steel and method for its composing, Lambert Academic Publishing, Germany, 2018, 120 p.
     Google Scholar
  9. Ukrainian Patent UA 114174, C2, (2017). Alloyed Low Hardenability Steel and Method of its Designing, Filed on Sep.23, 2013, File number: a 2013 11311, Published on June 25, 2016 in Bulletin No. 12, Legal day is May 10, 2017.
     Google Scholar
  10. Grossmann, M. A., 1964. Principles of Heat Treatment. Ohio: American Society for Metals, 302 pages.
     Google Scholar
  11. Totten, G.E., Bates, C.E., and Clinton, N.A., Handbook of Quenchants and Quenching Technology, ASM International, Materials Park, OH, 1993, 507 p.
     Google Scholar
  12. Kobasko, N.I., (2017). A method for optimizing chemical composition of steels to reduce radically their alloy elements and increase service life of machine components. EUREKA: Physics and Engineering, 1, 2017, pp. 3–12. doi: 10.21303/2461- 4262.2017.00253.
     Google Scholar
  13. Ferguson, B. L., Z. Li, and A. M. Freborg, Modeling Heat Treatment of Steel Parts, Computational Materials Science, Vol. 34, No. 3, 2005, pp. 274–281.
     Google Scholar
  14. Ferguson, B. L., A. M. Freborg, and Z. Li, Improving Gear Performance by Intensive Quenching, Proceedings of the 24th ASM Heat Treating Conference, 2007, pp. 156–162.
     Google Scholar
  15. Ferguson, B. L., and A. M. Freborg, A Design Tool for Tuning and Optimizing Carburizing and Heat Treat Process, SAE International Off-Highway Congress, Las Vegas, Nevada, March 19– 21, 2002, SAE Technical Paper Series 2002-01-1475.
     Google Scholar
  16. Inoue, T., and K. Arimoto, Development and Implementation of CAE System “Hearts” for Heat Treatment Simulation Based on tallo-thermo-mechanics, Journal of Materials Engineering and Performance, Vol. 16, No. 1, 1997, pp. 51–60.
     Google Scholar
  17. Bogatyrev, Ju.M., Shepelyakovskii, K.Z., Sklyarov, I.N., Cooling rate effect on crack formation at steel quenching, MiTOM, No. 11, 1967, pp. 15–22.
     Google Scholar