scholarly journals Loading Frequency Effect on Fatigue Crack Growth Rate in Low-Pressure Hydrogen Gas Environment in the Case of 6061-T6 Aluminum Alloy

2009 ◽  
Vol 75 (760) ◽  
pp. 1746-1753 ◽  
Author(s):  
Yasuji ODA ◽  
Hiroshi NOGUCHI ◽  
Kenji HIGASHIDA
2008 ◽  
Vol 44-46 ◽  
pp. 105-110
Author(s):  
Sen Ge ◽  
Zhong Li ◽  
J.G. Zhang ◽  
Y.C. Xiao ◽  
G.Q. Liu ◽  
...  

Fatigue crack growth rate experiments of center-cracked tension (CCT) specimens of the 2024-T3 aluminum alloy under constant-amplitude load in corrosive environment are carried out with 3 kinds of loading frequency. The fatigue crack growth rates in 3.5% NaCl solution are obtained by using seven-point incremental polynomial method. A probabilistic approach is presented for fatigue crack growth rate in corrosive environment with log-normal random variable model. The reliability analysis of crack propagation is conducted based on the experimental data. The crack exceedance probability at given service time and the distribution of the service time at given crack size are obtained by using the reliability analysis approach. The effect of loading frequency on crack propagation is studied. It is shown that the fatigue crack growth rate is increasing with loading frequency decreasing in corrosive environment. The predicted results by the presented method match the experimental results very well.


2007 ◽  
Vol 353-358 ◽  
pp. 174-177 ◽  
Author(s):  
Akiyoshi Hagihara ◽  
Yasuji Oda ◽  
Hiroshi Noguchi

In order to investigate the effects of testing frequency on the fatigue crack growth rate of 6061-T6 aluminum alloy in hydrogen gas environment, fatigue crack growth tests were carried out on specimens with small artificial holes in 0.18 MPa hydrogen gas or in 0.18 MPa nitrogen gas. It takes long time to test at low testing frequency, so in this study an accelerated test method was proposed and fatigue tests were carried out using this method. The fatigue crack growth rate in hydrogen gas environment accelerates compared with in nitrogen gas environment. The crack growth rate at lower testing frequency tends to higher.


1988 ◽  
Vol 133 ◽  
Author(s):  
G. M. Camus ◽  
D. J. Duquette ◽  
N. S. Stoloff

ABSTRACTStress-controlled fatigue tests and fatigue crack growth rate tests respectively have been carried out on two Ni3Al Cr/Zr alloys, IC 218 at 600°C and 800°C, and IC 221 at 800°C, in vacuum, at various test frequencies. Decreasing the test frequency and/or increasing the temperature leads to a decrease in the number of cycles to failure, and a gradual disappearance of a fatigue fracture zone. In fatigue crack propagation tests, the crack growth rate only decreases at the lowest frequency and remains constant in the major part of the frequency range investigated. The fatigue propagation mode in all cases is intergranular. These trends are shown in both cases to be related to a true creep component but, under fatigue crack growth test conditions, crack blunting intervenes gradually as the frequency is decreased, leading therefore to a less severe frequency effect.


Sign in / Sign up

Export Citation Format

Share Document