924 Study on Acoustic Emission Properties of A6061 Alloy during Tensile and Fatigue Testing : Influence of Grain Size

Electrical resistance (ER) is a relatively new approach for real-time monitoring and evaluating damage in SiC/SiC composites for a variety of loading conditions. In this study, ER of woven silicon carbide fiber-reinforced silicon carbide composite systems in their pristine and impacted state were measured under cyclic loading conditions at room and high temperature (1200C). In addition, modal acoustic emission (AE) was also monitored, which can reveal the occasion of matrix cracks and fiber. ER measurement and AE technique are shown in this study to be useful methods to monitor damage and indicate the failure under cyclic loading. Based on the slope of the ER evolution, an initial attempt has been made to develop a method allowing a critical damage phase to be identified. While the physical meaning of the critical point is not yet clear, it has the potential to allow the failure to be indicated at its early stage.

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Acoustic emission from wire ropes during proof load and fatigue testing

NDT & E International ◽

10.1016/j.ndteint.2006.07.005 ◽

2007 ◽

Vol 40 (1) ◽

pp. 94-101 ◽

Cited By ~ 33

Author(s):

G. Drummond ◽

J.F. Watson ◽

P.P. Acarnley

Keyword(s):

Acoustic Emission ◽

Fatigue Testing ◽

Wire Ropes

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Mechanical responses and acoustic emission properties of bolting system under short encapsulation cyclic thrust tests

International Journal of Fatigue ◽

10.1016/j.ijfatigue.2018.11.026 ◽

2019 ◽

Vol 121 ◽

pp. 39-54 ◽

Cited By ~ 3

Author(s):

Xiaowei Feng ◽

Nong Zhang ◽

Zhijie Wen

Keyword(s):

Acoustic Emission ◽

Emission Properties ◽

Mechanical Responses

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Effect of grain size on the mechanisms of plastic deformation in wrought Mg–Zn–Zr alloy revealed by acoustic emission measurements

Acta Materialia ◽

10.1016/j.actamat.2012.12.024 ◽

2013 ◽

Vol 61 (6) ◽

pp. 2044-2056 ◽

Cited By ~ 74

Author(s):

Alexei Vinogradov ◽

Dmitry Orlov ◽

Alexei Danyuk ◽

Yuri Estrin

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

Acoustic Emission ◽

Mechanisms Of Plastic Deformation ◽

Zr Alloy

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The influence of grain size on acoustic emission characteristic in commercial-purity zirconium during tensile deformation

Materials Science and Engineering A ◽

10.1016/j.msea.2015.04.081 ◽

2015 ◽

Vol 639 ◽

pp. 89-96 ◽

Cited By ~ 1

Author(s):

Lifei Li ◽

Zheng Zhang ◽

Gongtian Shen

Keyword(s):

Grain Size ◽

Acoustic Emission ◽

Tensile Deformation ◽

Emission Characteristic ◽

Commercial Purity

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The influence of aggregate grain size on the parameters of acoustic emission signals obtained from a three-point bending test on concrete specimens degraded by high-temperatures

Procedia Structural Integrity ◽

10.1016/j.prostr.2018.12.244 ◽

2018 ◽

Vol 13 ◽

pp. 1177-1182

Author(s):

Libor Topolář ◽

Šárka Keprdová ◽

Luboš Pazdera

Keyword(s):

Grain Size ◽

Acoustic Emission ◽

High Temperatures ◽

Bending Test ◽

Three Point Bending

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SOME ASPECTS OF ACOUSTIC EMISSION IN MAGNETIZATION (AEM) AND BARKHAUSEN NOISE (BN) SIGNALS; THE EFFECT OF GRAIN-SIZE IN A MILD STEEL.

Nondestructive Testing Communications ◽

10.1080/02780898808962134 ◽

1988 ◽

Vol 4 (2-3) ◽

pp. 83-83

Author(s):

Mamoru SHIBATA ◽

Hiroaki SASAKI

Keyword(s):

Grain Size ◽

Acoustic Emission ◽

Mild Steel ◽

Barkhausen Noise

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Reliability Improvement of Aluminum Wirebonds in High‐Power Igbt Modules

MRS Proceedings ◽

10.1557/proc-445-191 ◽

1996 ◽

Vol 445 ◽

Cited By ~ 1

Author(s):

Yujing Wu ◽

Gene Thome ◽

Timothy Scott Savage

Keyword(s):

Grain Size ◽

Crack Initiation ◽

High Power ◽

Fatigue Testing ◽

Temperature Cycling ◽

Grain Structure ◽

Aluminum Wire ◽

Significant Deterioration ◽

Temperature Cycles ◽

Igbt Modules

AbstractWirebonding is the weakest area of device packaging of power IGBT modules. Accelerated thermal fatigue testing causes cracks to form and propagate in the aluminum wirebond at the foot area. This study examined the relationship of the wirebond reliability and the aluminum wire grain structure, which can be affected by post‐wirebond heat treatment. A series of wirebonded IGBTs were annealed at a temperature range from 280°C to 400°C for up to 60 minutes. Wirebond shear strengths versus temperature cycles were examined. Cross‐sectional SEM was used to examine both aluminum grain size development by annealing and crack initiation and propagation in the wirebonds after temperature cycling. It was found that aluminum grain size was increased by post‐wirebond annealing. With temperature cycling, the wirebond shear strengths of the as‐wirebonded samples decrease rapidly, and lifted wirebonds were present after 1500 temperature cycles. The lifted wirebonds typically break within the aluminum wire near the wire/metallization interface. The shear strength of the wirebonds with post‐wirebond annealing showed no significant change even after 5000 temperature cycles, and there were no signs of significant deterioration of the wirebonds either. The wirebond crack initiation and growth rates were depressed substantially by larger aluminum grains. Annealing of the aluminum wire after wirebonding provided increased aluminum grain size resulting in improved reliability of the wirebonds of high power modules.

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