Shukayev S., Gladskiy М., Shubin S.
The National Technical University of Ukraine «Kyiv Polytechnic Institute», Kyiv, Ukraine (
EFFECT OF STRESS CONCENTRATION ON FATIGUE STRENGTH OF TYPE 20 STEEL
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 of specimens 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.
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