Effect of cold expansion on the fatigue life of Al 2024-T3 in double shear lap joints: Experimental and numerical investigations

The aim of this study is to examine the effect of the clearance and interference-fit on the fatigue life of composite lap joints in double shear, 3D finite element simulations have been performed to obtain stress (or strain) distributions around the hole due to interference fit using FEM package, Non-linear contact analyses are performed to examine the effects of the clearance and interference for titanium and composite lap joint. Fatigue tests were conducted for the titanium and composite lap joints with clearance fit and interference fit with 0.5, 1, and 1.5% nominal interference fit levels at different cyclic loads. The results shows that interference fit increases fatigue life compared to clearance fit specimens, the titanium and composite lap joint with 1% interference fit level has the better fatigue life.

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Cold Working Process on Hard Metal Stacked Assembly

Lecture Notes in Mechanical Engineering - Advances on Mechanics, Design Engineering and Manufacturing III ◽

10.1007/978-3-030-70566-4_8 ◽

2021 ◽

pp. 41-47

Author(s):

Guillaume Pichon ◽

Alain Daidie ◽

Adeline Fau ◽

Clément Chirol ◽

Audrey Benaben

Keyword(s):

Fatigue Life ◽

Hard Metal ◽

Fatigue Tests ◽

Cold Expansion ◽

Double Shear ◽

Shear Fatigue ◽

First Results ◽

Negative Effect ◽

Mechanical Performances ◽

Metallic Parts

AbstractDesigned for aeronautical and automotive applications, the split sleeve cold expansion process is used to improve the fatigue life of bolted metallic parts. Although its application has been well tested on aluminum assemblies, hard metal applications are still being studied. This paper presents experimental results of double bolt joint assemblies under double shear fatigue tests after stacked split sleeve cold expansion. The behaviors of two sizes of assemblies with different degrees of expansion are investigated. S-N curves are the main indicators of this study but thermal aspects are also investigated to observe fretting in the specimens as bolts are preloaded. Bolt tension is a major parameter in assembly regarding fatigue life. Interference between those two phenomena is at the heart of this paper. The first results show that stacked cold expansion has a negative effect on mechanical performances, as it deteriorates the fatigue life of the assembly. However, an examination of these results provides a coherent explanation for the loss of performance that occurs.

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Prediction of fatigue life in cold expanded Al-alloy 2024-T3 plates used in double shear lap joints

Journal of Mechanical Science and Technology ◽

10.1007/s12206-013-0322-5 ◽

2013 ◽

Vol 27 (5) ◽

pp. 1415-1425 ◽

Cited By ~ 12

Author(s):

Hadi Taghizadeh ◽

Tajbakhsh Navid Chakherlou ◽

Afshin Babaei Aghdam

Keyword(s):

Fatigue Life ◽

Lap Joints ◽

Al Alloy ◽

Double Shear

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Effect of bolt tightening on the fatigue behavior of GLARE double shear lap joints

Journal of Composite Materials ◽

10.1177/00219983211003315 ◽

2021 ◽

pp. 002199832110033

Author(s):

B Abazadeh ◽

HR Maleki

Keyword(s):

Fatigue Life ◽

Fatigue Behavior ◽

Fatigue Tests ◽

Lap Joints ◽

Clamping Force ◽

Test Results ◽

Load Range ◽

Double Shear ◽

Aluminum Sheets ◽

Aluminum Alloy 2024

In this paper, the effect of bolt torque tightening has been investigated on the fatigue behavior of GLARE in double shear lap configuration. To do so, experimental fatigue tests were conducted using GLARE3-5/4-0.4 specimens with applied torques of 0 (finger tightened), 2 and 4 Nm at different cyclic longitudinal load ranges to achieve the stress-life (S-N) curves. The results revealed that applying and increasing the clamping force enhances the fatigue life of the GLARE specimens. Furthermore, comparison of fatigue test results of GLARE and available monolithic aluminum alloy 2024-T3 plates indicated when the applied load range is low, the effect of clamping force is more noticeable in GLARE specimens due to longer fatigue crack growth life of GLARE. Also, the occurrence of fretting fatigue didn’t reduce the fatigue life of GLARE specimens considerably in contrary to aluminum sheets because of the laminated structure of GLARE. The obtained results can provide insights in designing bolted GLARE joints with superior fatigue in-service performance.

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