Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation Behavior
To monitor fatigue crack initiation and propagation, and to judge the fatigue damage status of ferromagnetic material, fatigue bending tests of four-point single edge notch bend (SENB4) specimens were carried out. Metal magnetic memory signals were measured during the whole fatigue process. The resu...
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doaj-c508568e65cb402d8ece9c005c7401a92020-11-25T01:42:58ZengMDPI AGMetals2075-47012019-01-01918910.3390/met9010089met9010089Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation BehaviorWei Zhou0Jianchun Fan1Jinlu Ni2Shujie Liu3College of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing 102200; ChinaCollege of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing 102200; ChinaCollege of Mechanical and Transportation Engineering, China University of Petroleum-Beijing, Beijing 102200; ChinaCNOOC Research Institute, Beijing 100029, ChinaTo monitor fatigue crack initiation and propagation, and to judge the fatigue damage status of ferromagnetic material, fatigue bending tests of four-point single edge notch bend (SENB4) specimens were carried out. Metal magnetic memory signals were measured during the whole fatigue process. The results showed that the fatigue process could be divided into four stages by observing the morphology of the fracture surface. With the increase of fatigue loading cycles, the tangential component of the magnetic field (Hx) and the normal component of the magnetic field (Hy) increased. At the notch Hx presented a “trough” shape and had a maximum value at the midpoint, while Hy at the notch rotated clockwise around the midpoint. Compared with the tangential characteristic parameters, the variation of normal characteristic parameters (i.e., maximum gradient value of Hy (Ky-max) and the variation range of Hy at the notch (∆Hyn), with the fatigue loading cycles are more similar to the variation of fatigue crack length with loading cycles), both Ky-max and ∆Hyn had a good linear relationship with fatigue crack length. Plastic deformation accumulated on both sides of the fatigue crack, and metal magnetic memory (MMM) signals measured from the specimens were able to indicate the location of the fatigue crack and the variation of the fatigue crack length. Furthermore, the distribution of magnetic signals was analyzed according to the theories of stress magnetization and magnetic flux leakage.http://www.mdpi.com/2075-4701/9/1/89X80 steelmetal magnetic memory testingfatigue crackstress magnetizationplastic deformation |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Wei Zhou Jianchun Fan Jinlu Ni Shujie Liu |
spellingShingle |
Wei Zhou Jianchun Fan Jinlu Ni Shujie Liu Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation Behavior Metals X80 steel metal magnetic memory testing fatigue crack stress magnetization plastic deformation |
author_facet |
Wei Zhou Jianchun Fan Jinlu Ni Shujie Liu |
author_sort |
Wei Zhou |
title |
Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation Behavior |
title_short |
Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation Behavior |
title_full |
Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation Behavior |
title_fullStr |
Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation Behavior |
title_full_unstemmed |
Variation of Magnetic Memory Signals in Fatigue Crack Initiation and Propagation Behavior |
title_sort |
variation of magnetic memory signals in fatigue crack initiation and propagation behavior |
publisher |
MDPI AG |
series |
Metals |
issn |
2075-4701 |
publishDate |
2019-01-01 |
description |
To monitor fatigue crack initiation and propagation, and to judge the fatigue damage status of ferromagnetic material, fatigue bending tests of four-point single edge notch bend (SENB4) specimens were carried out. Metal magnetic memory signals were measured during the whole fatigue process. The results showed that the fatigue process could be divided into four stages by observing the morphology of the fracture surface. With the increase of fatigue loading cycles, the tangential component of the magnetic field (Hx) and the normal component of the magnetic field (Hy) increased. At the notch Hx presented a “trough” shape and had a maximum value at the midpoint, while Hy at the notch rotated clockwise around the midpoint. Compared with the tangential characteristic parameters, the variation of normal characteristic parameters (i.e., maximum gradient value of Hy (Ky-max) and the variation range of Hy at the notch (∆Hyn), with the fatigue loading cycles are more similar to the variation of fatigue crack length with loading cycles), both Ky-max and ∆Hyn had a good linear relationship with fatigue crack length. Plastic deformation accumulated on both sides of the fatigue crack, and metal magnetic memory (MMM) signals measured from the specimens were able to indicate the location of the fatigue crack and the variation of the fatigue crack length. Furthermore, the distribution of magnetic signals was analyzed according to the theories of stress magnetization and magnetic flux leakage. |
topic |
X80 steel metal magnetic memory testing fatigue crack stress magnetization plastic deformation |
url |
http://www.mdpi.com/2075-4701/9/1/89 |
work_keys_str_mv |
AT weizhou variationofmagneticmemorysignalsinfatiguecrackinitiationandpropagationbehavior AT jianchunfan variationofmagneticmemorysignalsinfatiguecrackinitiationandpropagationbehavior AT jinluni variationofmagneticmemorysignalsinfatiguecrackinitiationandpropagationbehavior AT shujieliu variationofmagneticmemorysignalsinfatiguecrackinitiationandpropagationbehavior |
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1725033946643693568 |