Study of cycle life of a material in conditions of low-cycle fatigue and long-term strength


Experimental studies shows that the main parts - the shaft and the disks of gas turbine engines, working in the conditions of low-cycle fatigue and durability, have a durability far exceeding the resource identified by calculation based on the hypothesis of linear summation of damage. Therefore, further clarification is needed calculation methods, allowing greater use of the reserves of strength parts. The performed research studies the influence on the durability of the increasing duration of zero cycle of loading samples with a period of T=200 s. and the restraint at the maximum and minimum levels: Dtmax=120 s. and Dtmin=60 s. The studies were performed on a standard round specimens with the diameter of the working area of 7.5mm. Shown that when you restrain a loading there is in the material proceeds relaxation process, combined with a deforming cyclic hardening and increasing of the plastic deformation. It was found that the hypothesis of a linear summation of static and cyclic components of the damage in the conditions of low-cycle fatigue and long-term strength is not confirmed. The increasing of the restraint in the loading cycle under the load to Dtmax=20 s. or more leads to a significant increase - up to 94 % of the static component of damage. The research results obtained during cyclic and repeated static loading, helped to confirm and substantiate the existence of a previously unknown “Effect of cyclic hardening materials”, due to the duration of the maximum load in the cycle of loading.

About the authors

S. A. Bukatyi

Rybinsk State Aviation Technical University

Author for correspondence.

Doctor of Science (Engineering), Professor

Russian Federation

A. A. Okrugin

NPO “Saturn” Corporation, Rybinsk


Head of the Project

Russian Federation


  1. Sheremetiev A.V. Prediction of cyclic durability and the establishment of the resources of the basic parts of aircraft GTE // Аviatsionno-kosmicheskaya tekhnika i tekhnologiya. 2005. No. 8. P. 5. (In Russ.)
  2. Porter A.M., Bukatyi S.A., Vodalagin A.L. The research of the influence of the maximal stress duration in the cycle of loading upon the low-cycle fatigue and the long-term strength of the turbine shaft made of the material ЭИ 961-Ш // Vestnik of Samara State Aerospace University. 2009. No. 3(19), part 2. P. 55-63. (In Russ.)
  3. 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.)
  4. Demiyanushko I.V., Birger I.A. Raschet na prochnost' vrashchayushchikhsya diskov [The strength calculation of rotating discs]. Moscow: Mashinostroenie Publ., 1978. 247 p.
  5. Ronay M. Ustalost' vysokoprochnykh materialov. V kn.: Razrushenie [Fatigue of high-strength materials. In the book: The destruction]. V. 3. Moscow: Mir Publ., 1976. P. 471-527.
  6. Kuznetsov N.D., Zeitlin V.I. Ekvivalentnye ispytaniya gazoturbinnykh dvigateley [Equivalent testing of gas turbine engines]. Moscow: Mashinostroenie Publ., 1976. 216 p.



Abstract: 3224

PDF (Russian): 1922




  • There are currently no refbacks.

Copyright (c) 2015 VESTNIK of the Samara State Aerospace University

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies