Forecasting low-cycle fatigue life of gas-turbine engine parts by the method of equivalent tests for specimens with stress concentrator under extension-compression

Abstract


A method of low-cycle fatigue equivalent tests based on the application of test specimens whose stress-strain state shall be similar to the stress-strain state of the part to be investigated is proposed in the paper. The stiffness ratio of the stressed state is used as the similarity criterion of stress and strain state of the specimens and the part. The method was successfully applied on the low-pressure compressor disk of a gas turbine engine. Specimens with a circular cross section and a V-concentrator were used as equivalent specimens. The tests were carried out as follows: the specimens were tested under stretching and compression for the zero-to-compression stress cycle; the disks were tested on a dedicated test bench with the spin-up of up to 5000 rpm. The proposed method of equivalent tests makes it possible to forecast low-cycle fatigue life of large-sized critical parts whose full-scale tests cannot be carried out. The method can also be used to assess the high-cycle fatigue life of parts and to forecast their long-term strength. The obtained equations make it possible to design and optimize the construction of aviation parts: the permissible value of strain rate in the most strained area of the part can be determined by the specified fatigue life.


About the authors

S. A. Bukatyy

Soloviev Rybinsk State Aviation Technical University

Author for correspondence.
Email: bukaty_sa@mail.ru

Russian Federation

Doctor of Science (Engineering), Professor of the Department of Applied Mechanics

A. V. Pakhomenkov

Public Joint-Stock Company UEC-Saturn

Email: aleksandr.pakhomenkov@uec-saturn.ru

Russian Federation

Chief of Design Department of Strength

G. A. Solntsev

Public Joint-Stock Company UEC-Saturn

Email: Solntsev_g_a_233@mail.ru

Russian Federation

Engineer of the Design Department of Strength

A. S. Bukatyy

Samara National Research University

Email: bukaty@inbox.ru

Russian Federation

Candidate of Science (Engineering), Assistant Professor of the Department of Strength of Materials

References

  1. Manson S.S. Fatigue: a complex subject – some simple approximations. Experimental Mechanics. 1965. V. 5, Iss. 4. P. 193-226. doi: 10.1007/bf02321056
  2. Dem'yanushko I.V., Birger I.A. Raschet na prochnost’ vrashchayushchikhsya diskov [Stress calculation of rotating discs]. Moscow: Mashinostroenie Publ., 1978. 247 p.
  3. Birger I.A., Shorr B.F., Iosilevich G.B. Raschet na prochnost' detaley mashin: spravochnik [Stress calculation of machine parts: reference book]. Moscow: Mashinostroenie Publ., 1979. 702 p.
  4. Muralidharan U., Manson S.S. A modified universal slopes equation for estimation of fatigue characteristics of metals. Journal of Engineering Materials and Technology, Transactions of the ASME. 1988. V. 110, Iss. 1. P. 55-58. doi: 10.1115/1.3226010
  5. Muratov R.Kh. Mnogokriterial'noe optimal'noe proektirovanie osnovnykh detaley rotorov GTD dlya ozhidaemykh usloviy ekspluatatsii. Avtoref. dis. … kand. tekh. nauk [Multicriterion optimum design of gas turbine engine rotor main parts for anticipated operating conditions. Extended abstract of Cand. Sci. (Eng.) Dissertation]. Perm', 2004. 16 p.
  6. Porter A.M., Bukatyi S.A., Okrugin A.A. Study of the processes of damage accumulation and fracture of gas turbine shaft and disc from materials of EI-961 depending on the duration of action of the maximum stress in the cycle of loading. Vestnik RGATU. 2008. No. 2 (14). P. 65-74. (In Russ.)
  7. Sheremet'ev A.V. Forecasting of fatigue life and determining the endurance of aircraft gas turbine engine’s main parts. Aerospace Technic and Technology. 2005. No. 8 (24). P. 45-50. (In Russ.)
  8. Bukaty A.S., Bukaty S.A. The analysis criteria development for the stress-strain state of gas turbin engine parts in the elastoplastic region. Sbornik materialov mezhdunarodnoy nauchno-tekhnicheskoy konferentsii «Problemy i perspektivy razvitiya dvigatelestroyeniya». Part 2. Samara: Samara University, 2016. P. 66-68. (In Russ.)
  9. Bukaty A.S., Bukaty S.A., Andreev I.B. Optimization of GTE essential parts design on the basis of stress criteria. Vestnik RGATU. 2016. No. 4(39). P. 7-13. (In Russ.)
  10. Smirnov-Alyaev G.A. Mekhanicheskie osnovy plasticheskoy obrabotki metallov. Inzhenernye metody [Mechanical principles of plastic working of metals]. Leningrad: Mashinostroenie Publ., 1968. 272 p.

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