PSI - Issue 56

Zbigniew Marciniak et al. / Procedia Structural Integrity 56 (2024) 131–137 Author name / Structural Integrity Procedia 00 (2019) 000–000

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3. Results and discussion t h aDnuk rsi nt og wt hhei cthe st thse, tahnea ldy es fi so romf at ht ieo nb eahnadv i sotur re sosf ct ho eu rtseesst ewd esraemrpelceosr wd eads cpoons st ii nb ul eo. uTshl ye, taess tes xshhi bo iwt eedd idni f Ff ei gr e. n5t, ts rhaonws ieedn ta rceyscpl iocnssoefst eonf i tnhge bme ha at evri ioaul rd(eFpi eg n. 5d ai n) ,g wo hn i ct hh ewsat rs aei nv i dl eevnetl . bAy t t thhee dt ewc or ehaisgeh iens ts tl or ea sds l ae mv epl sl i, t tuhdee saanmd ptlhe es dl eevgeel ns , ewr aht ei or ne ot hf et hvea hl uyes toefr ep sl ai ss tl iocodpes f tohr rmo autgi ho no uwt at hs es mt e as tl l ,( Fa i gs .t a6b) l. eO bnethhaev oi ot hu er rwhaasn odb, sf oerr vt eh de t( wF iog . l o5 wb )e, sat nsdt r tahi ne stress level was constant until the crack appeared, as can be inferred from the hysteresis loops shown in Fig. 7.

Fig. 5. Stress changes during the tests for the maximum strain amplitude: a) 1%, b) 0.5%.

Fig. 6. Examples of the hysteresis loops collected in the tests at a maximum strain amplitude of 1% for different stages of fatigue life: a) at the beginning, b) in the middle, c) before failure.