Exploiting fractal features to determine fatigue crack growth rates of metallic materials

Kód výsledku v IS VaVaI

RIV/46747885:24620/22:00010685 - isvavai.cz

Výsledek na webu

https://www.sciencedirect.com/science/article/pii/S0013794422003228?via=ihub

DOI - Digital Object Identifier

10.1016/j.engfracmech.2022.108589

Jazyk výsledku

angličtina

Název v původním jazyce

Exploiting fractal features to determine fatigue crack growth rates of metallic materials

Popis výsledku v původním jazyce

An alternative approach to the classical fracture mechanics equation to quantify the fatigue crack growth rate is proposed and examined. The method exploits the fractal features of the propagating fatigue crack. The reference crack growth response of AISI 410 martensitic stainless steel is established using compact tension C(T) specimens. Fractal analysis of microscopic images along the edge length of the crack establishes the fractal dimensions, d(F) of the fatigue crack. The box-counting algorithm is developed for the fractal analysis based on optical images of the crack at 100X magnification and the resolution of 1090 pixels/mm. Results show that the crack initially exhibits a Euclidean nature (d(F) approximate to 1). The fractal dimension increases steadily with increasing crack length in the Paris crack growth rate region with 1.05 b d(F) b 1.24. The corresponding stress intensity factor range varies between 18 b= Delta K-I b= 40 MPa root m. The fractal dimension, d(F) correlates linearly with the normalized stress intensity factor range, Delta K/K(IC)within the Paris crack growth region. This enables the multifractal fatigue crack growth rate equation to be established in terms of the fractal dimension, Paris coefficient and exponent, and fatigue fracture properties of the material. The fatigue crack growth rate of the material could then be determined using the multifractal fatigue crack growth rate model without requiring the geometry factor of the crack.

Název v anglickém jazyce

Exploiting fractal features to determine fatigue crack growth rates of metallic materials

Popis výsledku anglicky

An alternative approach to the classical fracture mechanics equation to quantify the fatigue crack growth rate is proposed and examined. The method exploits the fractal features of the propagating fatigue crack. The reference crack growth response of AISI 410 martensitic stainless steel is established using compact tension C(T) specimens. Fractal analysis of microscopic images along the edge length of the crack establishes the fractal dimensions, d(F) of the fatigue crack. The box-counting algorithm is developed for the fractal analysis based on optical images of the crack at 100X magnification and the resolution of 1090 pixels/mm. Results show that the crack initially exhibits a Euclidean nature (d(F) approximate to 1). The fractal dimension increases steadily with increasing crack length in the Paris crack growth rate region with 1.05 b d(F) b 1.24. The corresponding stress intensity factor range varies between 18 b= Delta K-I b= 40 MPa root m. The fractal dimension, d(F) correlates linearly with the normalized stress intensity factor range, Delta K/K(IC)within the Paris crack growth region. This enables the multifractal fatigue crack growth rate equation to be established in terms of the fractal dimension, Paris coefficient and exponent, and fatigue fracture properties of the material. The fatigue crack growth rate of the material could then be determined using the multifractal fatigue crack growth rate model without requiring the geometry factor of the crack.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20302 - Applied mechanics

Projekt

EF16_025/0007293: Modulární platforma pro autonomní podvozky specializovaných elektrovozidel pro dopravu nákladu a zařízení

Návaznosti

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

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

ENGINEERING FRACTURE MECHANICS

ISSN

0013-7944

e-ISSN

—

Svazek periodika

270

Číslo periodika v rámci svazku

JUL

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

15

Strana od-do

—

Kód UT WoS článku

000833424200008

EID výsledku v databázi Scopus

2-s2.0-85131464028