Notch suppression on martensitic stainless steels by Laser Shot Peening

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F26722445%3A_____%2F23%3AN0000219" target="_blank" >RIV/26722445:_____/23:N0000219 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Notch suppression on martensitic stainless steels by Laser Shot Peening

Popis výsledku v původním jazyce

Most fatigue cracks initiate at defects (notch) that create stress concentrators and cause the weakness of the whole component. The notch effect causes an increase tensile stress at the notch tip and improves conditions for crack nucleation. Under fatigue loading, the notch effect causes a significant decrease in the fatigue life of a component. Detrimental stress distribution caused by notches can be eliminated by laser shock peening (LSP) due to its ability to induce compressive residual stresses which prevent crack initiation. The high cycle fatigue (HCF) tests were performed on martensitic stainless steel Böhler T552. The specimen type for HCF was of hourglass type with 5 mm diameter. Tested specimens were in 3 modifications: specimen with smooth surface without defect and peening, specimen with artificial defect (notch) in the middle of minimum diameter and specimen with notch, which was peened with LSP technology. LSP treatment was performed in HiLASE Center, with L2 system – Bivoj. The fatigue tests were performed on resonant testing machine (static preload 300 MPa, frequency 120 Hz and test temperature 22 °C). Fractographic analysis of the fracture surfaces was performed. The LSP increased the stress amplitude of fatigue strength more than three times on specimens with defect. Presented at 8thICLPRP conference, Gyeongju, Korea.

Název v anglickém jazyce

Notch suppression on martensitic stainless steels by Laser Shot Peening

Popis výsledku anglicky

Most fatigue cracks initiate at defects (notch) that create stress concentrators and cause the weakness of the whole component. The notch effect causes an increase tensile stress at the notch tip and improves conditions for crack nucleation. Under fatigue loading, the notch effect causes a significant decrease in the fatigue life of a component. Detrimental stress distribution caused by notches can be eliminated by laser shock peening (LSP) due to its ability to induce compressive residual stresses which prevent crack initiation. The high cycle fatigue (HCF) tests were performed on martensitic stainless steel Böhler T552. The specimen type for HCF was of hourglass type with 5 mm diameter. Tested specimens were in 3 modifications: specimen with smooth surface without defect and peening, specimen with artificial defect (notch) in the middle of minimum diameter and specimen with notch, which was peened with LSP technology. LSP treatment was performed in HiLASE Center, with L2 system – Bivoj. The fatigue tests were performed on resonant testing machine (static preload 300 MPa, frequency 120 Hz and test temperature 22 °C). Fractographic analysis of the fracture surfaces was performed. The LSP increased the stress amplitude of fatigue strength more than three times on specimens with defect. Presented at 8thICLPRP conference, Gyeongju, Korea.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

20501 - Materials engineering

Projekt

<a href="/cs/project/TK05010007" target="_blank" >TK05010007: Progresivní technologie preventivní údržby kritických komponent jaderných zařízení na bázi zlepšení povrchového napětí (Surface Stress Improvement - SSI)</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů