Investigation on fatigue crack propagation law of the crack perpendicular to interface for Zr/Ti/steel composite plate

2022 ◽  
Vol 195 ◽  
pp. 104594
Author(s):  
Binbin Zhou ◽  
Liangfu Zhou ◽  
Le Chang ◽  
Changyu Zhou ◽  
Cheng Ye ◽  
...  
2014 ◽  
Vol 891-892 ◽  
pp. 911-916
Author(s):  
Pavel Hutař ◽  
Ivo Kuběna ◽  
Miroslav Šmíd ◽  
Martin Ševčík ◽  
Tomáš Kruml ◽  
...  

The oxide dispersion strengthened (ODS) steels are widely studied as possible candidate material for fission and fusion technology. Due to application of the ODS materials, mainly low cycle fatigue is important. Therefore, small crack initiation and propagation for rather high stress amplitude are in focus. The main aim of the presented work is description of the small fatigue crack propagation for ODS-EUROFER steel. Due to limited quantity of ODS steel special miniaturized cylindrical specimens for fatigue testing were designed. Crack propagation law based on plastic part of J-integral is presented and applied for mentioned material. The resulting fatigue crack propagation rates for ODS-EUROFER steel and EUROFER 97 are compared and discussed.


Author(s):  
Xin Wang

It has been observed that the loss of crack tip constraint leads to enhanced resistance to both cleavage and ductile tearing. Recent developments on constraint-based fracture mechanics have enabled the practical assessment of defective components including the constraint effect. In fatigue analyses, it is common practice to use the Paris crack propagation law, which is based on the stress intensity factor alone. Although in recent years several research attempts have been made to investigate the effect of constraint on fatigue, how to quantify the effect of crack tip constraint on the fatigue crack propagation rate is still an open issue. In this paper, the effect of crack tip constraint on the fatigue crack propagation of small cracks at notched plates is investigated. A fatigue crack propagation rate model developed earlier which incorporates both low and high constraint conditions is used. It is shown that the effect of constraint on crack propagation rate is significant when the crack is small (within the stress concentration of the notches). This effect can be accounted for by using the fatigue crack propagation rate model.


1991 ◽  
Vol 113 (4) ◽  
pp. 215-221
Author(s):  
C. Ihara ◽  
T. Misawa

The stochastic models for the fatigue damage phenomena are proposed. They describe the uncertainty caused by inhomogeneity of materials for fatigue crack propagation of metals and fatigue damage of carbon fiber composite (CFRP). The models are given by the stochastic differential equations derived from the randomized Paris-Erdogan’s fatigue crack propagation law and Kachonov’s equation of fatigue damage. The sample paths and life distribution of fatigue crack propagation in metals or of damage accumulation in CFRP are obtained by using the solution of the stochastic differential equation and the probability density function, respectively. These theoretical results are compared with the actual experiments—fatigue crack propagation of high tensile strength steel APFH 60 and fatigue test for a carbon eight-harness-satin/epoxy laminate—through numerical experiments.


Author(s):  
Mario Guagliano ◽  
Andrea Piazza ◽  
Laura Vergani

The problem of the rolling contact fatigue crack propagation in gear teeth is dealt with. An approach based on the weight function method for the determination of KI and KII of internal cracks was developed. The effect of the contact and of the friction between the crack faces was taken into consideration by using approximate relations. The results were compared with the ones obtained by finite element analyses and the agreement was found satisfactory. By means of the determined weight function several analyses were performed and an interpolating function of KII versus the crack length were found. An approach for rolling contact fatigue crack propagation prediction based on the obtained solution and on a short crack propagation law was developed and implemented in a computational routine. The results are critically discussed.


2010 ◽  
Vol 659 ◽  
pp. 49-54
Author(s):  
János Lukács

There are different documents and standards containing fatigue crack propagation limit or design curves and rules for the prediction of crack growth. The background of the curves and the calculations consist of two basic parts: statistical analysis of numerous experiments and a fatigue crack propagation law. The research work aimed to measure basic data for limit curves on austenitic stainless steel, in corrosive environment and at elevated temperatures, and to determine the design curves based on statistical analysis of measured data and a fatigue crack propagation law. Experiments were performed on modified CT specimens, in water solution and at two different temperatures. The fatigue crack growth tests were executed by constant load amplitude method. In order to study the hold time effect, fatigue crack growth tests were terminated and hold time period was applied. It can be concluded that the modified CT specimens are suitable for fatigue crack growth tests in corrosive environment; the fatigue crack propagation characteristics are different at different testing temperatures; and stable crack propagation and/or crack tip blunting can be detected during the hold time period at the used higher testing temperature.


Sign in / Sign up

Export Citation Format

Share Document