DOI: https://doi.org/10.20535/2305-9001.2012.65.38237

EFFECT OF STRESS CONCENTRATION ON FATIGUE STRENGTH OF TYPE 20 STEEL

С. М. Шукаєв, М. М. Гладский, С. М. Шубін

Abstract


The effect of stress concentration on fatigue strength of type 20 steel was investigated. The fatigue tests were carried out on thin-walled tubular smooth specimens and specimens containing a circular hole. The fatigue strength of specimens with stress concentrators was lower than that of smooth specimens. The effect of stress concentration on fatigue life ofspecimens was the largest on test base of 106 cycles. With the increase in the amplitude of stress this effect decreased and reduced to naught in the range of quasi-static fracture. The S-N approach as well as Neuber’s rule and Glinka’s rule were used in this study for fatigue life prediction for notched specimens in the range of low cycle fatigue. The Neuber’s rule and S-N approach was found to correlate data well

Keywords


fatigue strength; notch effect; S–N approach; type 20 steel; tubular specimens

References


1. GOST 1050-88 Prokat sortovoj, kalibrovannyj, so special'noj otdelkoj poverhnosti iz uglerodistoj kachestvennoj konstrukcionnoj stali (Carbon structural quality steel gauged bars with special surface finish. General specifications). Moscow: Standartform, 2010, 24 p.

2. GOST 25.504-82 Raschety i ispytanija na prochnost'. Metody rascheta harakteristik soprotivlenija ustalosti (Strength calculation and testing. Methods of fatigue strength behaviour calculation). Moscow: Gosudarstvennyj komitet SSSR po standartam,1982, 54 p.

3. Hejvud R.B. Proektirovanie s uchetom ustalosti [Designing for fatigue] / per. s angl. Pod red. I.F. Obrazcova. Moscow.: Mashinostroenie, 1969, 504 p.

4. Kollinz Dzh. Povrezhdenie materialov v konstrukcijah. Analiz, predskazanie, predotvrawenie [Failure of materials in Mechanical Design] / per. s angl. – Moscow: Mir, 1984, 624 p.

5. H. Neuber. Theory of stress concentration for shear-strained prismatical bodies with arbitrary non-linear stress-strain law. Trans. ASME, J. Appl. Mech. 1961;28:544-50.

6. Molski, K. and Glinka, G. A method of elastic-plastic stress and strain calculation at a notch root. Mater. Sci. Engng, 1981, 50, 93–100.

7. Glinka, G. Energy density approach to calculation of inelastic strain–stress near notches and cracks. Engng Fracture Mechanics, 1985, 22(3), 485–508.

8. Glinka, G. Calculation of inelastic notch-tip strain–stress history under cyclic loading. Engng Fracture Mechanics1985, 22(5), 839–854.

9. Shang DG, Yao WX, Wang DJ. A new approach to the determination of fatigue crack initiation size. Int J Fatigue 1998;20(9):683-7.


GOST Style Citations


1.            ГОСТ 1050-88 Прокат сортовой, калиброванный, со специальной отделкой поверхности из углеродистой качественной конструкционной стали.- М.: Стандартформ, 2010. - 24 с.

 

2.            ГОСТ 25.504-82 Расчеты и испытания на прочность. Методы расчета характеристик сопротивления усталости. .- М.: Государственный комитет СССР по стандартам,1982. - 54 c.

 

3.            Хейвуд Р.Б. Проектирование с учетом усталости / пер. с англ. Под ред. И.Ф. Образцова. М.:  Машиностроение. 1969. - 504 с.

 

4.            Коллинз Дж. Повреждение материалов в конструкциях. Анализ, предсказание, предотвращение: Пер. с англ. – М.: Мир, 1984.-624 с.

 

5.            H. Neuber. Theory of stress concentration for shear-strained prismatical bodies with arbitrary non-linear stress-strain law. Trans. ASME, J. Appl. Mech. 1961;28:544-50.

 

6.            Molski, K. and Glinka, G. A method of elastic-plastic stress and strain calculation at a notch root. Mater. Sci. Engng, 1981, 50, 93–100.

 

7.            Glinka, G. Energy density approach to calculation of inelastic strain–stress near notches and cracks. Engng Fracture Mechanics, 1985, 22(3), 485–508.

 

8.            Glinka, G. Calculation of inelastic notch-tip strain–stress history under cyclic loading. Engng Fracture Mechanics1985, 22(5), 839–854.

 

9.            Shang DG, Yao WX, Wang DJ. A new approach to the determination of fatigue crack initiation size. Int J Fatigue 1998;20(9):683-7.





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