scholarly journals Effect of Water Vapor on Fatigue Crack Growth in 7475-T651 Aluminum Alloy Plate

2008 ◽  
pp. 513-513-21 ◽  
Author(s):  
DL Dicus
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Crack ◽  
Water Vapor ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Alloy Plate ◽  
Effect Of Water ◽  
Aluminum Alloy Plate

Grey Relational Grade Analysis between Vickers Hardness and Fatigue Crack Growth Data of 2024-T351 Aluminum Alloy

2012 ◽  
Vol 476-478 ◽  
pp. 2435-2439 ◽  
Author(s):  
Chih Chung Ni
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Vickers Hardness ◽  
Compact Tension ◽  
Growth Data ◽  
Alloy Plate ◽  
Grey Relational Grade ◽  
Grey Relational

Compact tension specimens cut from 2024-T351 aluminum-alloy plate were used for Vickers hardness tests under low-force scale and then for fatigue crack growth tests under sinusoidal loads, and the scattered data sets obtained including Vickers hardness, initiation cycle and specimen life, exponent m and intercept C of Paris-Erdogan law were collected as a factor set with five factor series for analysis of grey relational grade. Nominal value method was adopted for the preprocess referred to as grey relational generation to obtained new factor series, and then Hsia’s method was used to calculate the grey relational grades among new factor series. The analyzed result named global grey relational grade in matrix form with dimension of shows three main findings: (1) Vickers hardness has the largest influence on specimen life, and vice versa. (2) Vickers hardness, specimen life, and m have a large influence on each other. (3) C has the least influence on any other factors, and vice versa.

scholarly journals SVR Prediction Algorithm for Crack Propagation of Aviation Aluminum Alloy

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Jincai Chang ◽  
Zhihang Wang ◽  
Qingyu Zhu ◽  
Zhao Wang
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Length ◽  
Crack Growth ◽  
Fatigue Testing ◽  
Testing Machine ◽  
Prediction Algorithm ◽  
Support Vector ◽  
Alloy Plate

Aluminum alloy material is an important component material in the safe flight of aircraft. It is very important and necessary to predict the fatigue crack growth between holes of aviation aluminum alloy materials. At present, the investigation on the prediction of the cracks between two holes and multiholes is a key problem to be solved. Due to the fact that the fatigue crack growth test of aluminum alloy plate with two or three holes was carried out by the MTS fatigue testing machine, the crack length growth data under different test conditions were obtained. In this paper, support vector regression (SVR) was used to fit the crack data, and the parameters of SVR are optimized by the grid search algorithm at the same time. And then the model of SVR to predict the crack length was established. Discussion on the results shows that the prediction model is effective. Furthermore, the crack growth between three holes was predicted accurately through the model of the crack law between two holes under the same load form.

Fracture Mechanics Parameters for a 5083-0 Aluminum Alloy at Low Temperatures

1977 ◽  
Vol 99 (4) ◽  
pp. 306-312 ◽  
Author(s):  
R. L. Tobler ◽  
R. P. Reed
Keyword(s):  
Fracture Toughness ◽  
Aluminum Alloy ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Growth Rates ◽  
Rolling Direction ◽  
Integral Test ◽  
Alloy Plate ◽  
Crack Growth Rates

The fatigue crack growth and fracture resistance of a 5083-0 aluminum alloy plate were investigated at four temperatures in the ambient-to-cryogenic range—295, 111, 76, and 4 K. J-integral test methods were applied using compact specimens 3.17 cm thick, and the value of J required to initiate crack extension (JIc) is reported as an index of fracture toughness. The fracture toughness was orientation dependent, with anisotropy accounting for JIc variations of up to a factor of 2. For specimens having fracture planes parallel to the rolling direction, JIc increases progressively from 9 to 25 kJm−2 as temperature decreases between 295 and 4 K. In contrast, the fatigue crack growth rates (da/dN) are insensitive to specimen orientation. The fatigue crack growth rates at cryogenic temperatures are up to 10 times lower than in air at room temperature, but are virtually constant between 111 and 4 K.

Guided Wave Acoustic Emission from Fatigue Crack Growth in Aluminium Plate

2006 ◽  
Vol 13-14 ◽  
pp. 23-28 ◽  
Author(s):  
C.K. Lee ◽  
Jonathan J. Scholey ◽  
Paul D. Wilcox ◽  
M.R. Wisnom ◽  
Michael I. Friswell ◽  
...  
Keyword(s):  
Acoustic Emission ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Elastic Waves ◽  
Fatigue Cracks ◽  
Guided Wave ◽  
Experimental Results ◽  
Multiple Reflections ◽  
Alloy Plate

Acoustic emission (AE) testing is an increasingly popular technique used for nondestructive evaluation (NDE). It has been used to detect and locate defects such as fatigue cracks in real structures. The monitoring of fatigue cracks in plate-like structures is critical for aerospace industries. Much research has been conducted to characterize and provide quantitative understanding of the source of emission on small specimens. It is difficult to extend these results to real structures as most of the experiments are restricted by the geometric effects from the specimens. The aim of this work is to provide a characterization of elastic waves emanating from fatigue cracks in plate-like structures. Fatigue crack growth is initiated in large 6082 T6 aluminium alloy plate specimens subjected to fatigue loading in the laboratory. A large specimen is utilized to eliminate multiple reflections from edges. The signals were recorded using both resonant and nonresonant transducers attached to the surface of the alloy specimens. The distances between the damage feature and sensors are located far enough apart in order to obtain good separation of guided-wave modes. Large numbers of AE signals are detected with active fatigue crack propagation during the experiment. Analysis of experimental results from multiple crack growth events are used to characterize the elastic waves. Experimental results are compared with finite element predictions to examine the mechanism of AE generation at the crack tip.

Micromechanisms of multistage fatigue crack growth in a high-strength aluminum alloy

2007 ◽  
Vol 55 (6) ◽  
pp. 1975-1984 ◽  
Author(s):  
Y. Xue ◽  
H. El Kadiri ◽  
M.F. Horstemeyer ◽  
J.B. Jordon ◽  
H. Weiland
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
High Strength ◽  
High Strength Aluminum Alloy
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