Probabilisticapproach foranalitically-determined fatigue curve

• Autorzy: Strzelecki P. , Sempruch J.
• Języki publikacji: EN

Abstrakty

EN

When a new machine element is to be designed, the dimension of the element must be defined by calculating fatigue strength or life. To calculate it, fatigue characteristic of this part must be known. To acquire the information on such properties, the analytical method can be applied. Fatigue curve plotted that way is corresponding to 50% probability of the element failure. However, for engineering calculations there must be used a characteristic curve of 95% level of reliability or higher. The paper presents the method of the translocation of the fatigue curve, applying the analytical method to the technical requirements of probability. To verify this approach, an experiment was carried out to get fatigue characteristics of material C45+C and 42CrMo4 and comparisons were made for that estimated curve with the characteristics provided by the analytical method to require reliability. The fatigue test was made using smooth specimen and loaded by rotating bending. The comparison performed indicates sufficient analytical curve as compared with the characteristics estimated from the experiment. One shall note that the reliability coefficient can be used to substitute the safety coefficient which can assume a large value as there is no applicable knowledge available.

Słowa kluczowe

EN

high-cycle fatigue strength; fatigue plots; analytical methods of estimating Wöhler characteristics

• Wydawca: Faculty of Ocean Engineering and Ship Technology, Gdańsk University of Technology
• Czasopismo: Journal of Polish CIMAC
• Rocznik: 2013
• Tom: Vol. 8, no 3
• Strony: 103--108
• Opis fizyczny: Bibliogr. 7 poz., wykr., tab.

Twórcy

autor

Strzelecki P.

• University of Technology and Life Sciences Faculty of Mechanical Engineering ul. Prof. S. Kaliskiego 7, 85-789 Bydgoszcz tel.: [phone]

autor

Sempruch J.

Bibliografia

• 1] Kocańda S., Szala J., Podstawy obliczeń zmęczeniowych, PWN, Warszawa, 1997.
• [2] Lee Yung-Li, Pan Jwo, Hathaway R. B., Barkey M. E., Fatigue testing and analysis, University of Alabama, Elsevier 2005.
• [3] Neimitz A., Dzioba I., Graba M., Okrajni J., Ocena wytrzymałości, trwałości i bezpieczeństwa pracy elementów konstrukcyjnych zawierających defekty, Politechnika Świętokrzyska, Kielce 2008.
• [4] Niezgodziński M.E., Niezgodziński T., Wzory wykresy i tablice wytrzymałościowe, wyd. 9, Warszawa WNT, 2004.
• [5] Pook L., Metal fatigue what it is. Why it matters, London Springer 2009,
• [6] Strzelecki P., Sempruch J., Experimental Verification of the Analytical Method for Estimated S-N Curve in Limited Fatigue Life. Materials Science Forum, Vol. 726, 2012, pp. 11-16.
• [7] Strzelecki P., Sempruch J., Modification of selected methods of rapid determination of fatigue characteristics in the range of limited fatigue life, Journal of Polish Cimac Selected problems of designing and operating technical systems Vol. 6 No 3; 2011, pp. 289-296.