Fatigue of Friction Stir Welded Lap Joints with Sealants

"A lack of understanding of corrosion fatigue in friction stir welded aluminum joints prevents friction stir welding from being implemented in aerospace applications. Fatigue testing reveals a 60-75% reduction in the fatigue life of friction stir welded aluminum lap joints immersed in 3.5% NaCl solution (corrosion fatigue) compared with that of lap joints tested in ambient air. The loss in fatigue life is attributed to accelerated fatigue cracking due to hydrogen environment embrittlement. Two polymer sealant candidates are investigated: silicone rubber and nylon-11. Both sealant candidates can be applied prior to welding and seal the faying surface gaps in lap joints upon welding. The rubber sealant cures at room temperature after welding and can be welded with the same parameters as without the sealant. The 50% sample population corrosion fatigue life is increased by 22% with the use of the rubber sealant, but the effectiveness of the rubber sealant is limited by its cohesive mechanical properties, e.g. elongation to failure. In ambient fatigue, the nylon sealed welds exhibit twice the 50% sample population fatigue life of other welds. Finite element modeling predicts a reduction in the stresses in the weld due the stiffness contribution of the nylon sealant. The effectiveness of the nylon sealant is limited by its adhesive bond strength. When immersed in water, as in corrosion fatigue, the adhesive bond strength is reduced, the sealant bond fails within 500 fatigue cycles, and the mechanical benefits of the nylon sealant are negated. The corrosion fatigue life of nylon sealed welds is 26% less than that of welds without sealant because of the more severe hook defect associated with hotter welding conditions required to melt the nylon. Finite element modeling results indicate an increase in stress intensity factors of about 10% in welds with more severe hook defects--Abstract, leaf iii.

Produk Detail:

  • Author : Kenneth Thomas Nathaniel Doering
  • Publisher : Anonim
  • Pages : 256 pages
  • ISBN :
  • Rating : 4/5 from 21 reviews
CLICK HERE TO GET THIS BOOKFatigue of Friction Stir Welded Lap Joints with Sealants

Fatigue of Friction Stir Welded Lap Joints with Sealants

Fatigue of Friction Stir Welded Lap Joints with Sealants
  • Author : Kenneth Thomas Nathaniel Doering
  • Publisher : Unknown Publisher
  • Release : 17 October 2021
GET THIS BOOKFatigue of Friction Stir Welded Lap Joints with Sealants

"A lack of understanding of corrosion fatigue in friction stir welded aluminum joints prevents friction stir welding from being implemented in aerospace applications. Fatigue testing reveals a 60-75% reduction in the fatigue life of friction stir welded aluminum lap joints immersed in 3.5% NaCl solution (corrosion fatigue) compared with that of lap joints tested in ambient air. The loss in fatigue life is attributed to accelerated fatigue cracking due to hydrogen environment embrittlement. Two polymer sealant candidates are investigated: silicone rubber

Fatigue in Friction Stir Welding

Fatigue in Friction Stir Welding
  • Author : J. Brian Jordon,Robert Amaro,Paul Allison,Harish Rao
  • Publisher : Butterworth-Heinemann
  • Release : 27 February 2019
GET THIS BOOKFatigue in Friction Stir Welding

Fatigue in Friction Stir Welding provides knowledge on how to design and fabricate high performance, fatigue resistance FSW joints. It summarizes fatigue characterizations of key FSW configurations, including butt and lap-shear joints. The book's main focus is on fatigue of aluminum alloys, but discussions of magnesium, steel, and titanium alloys are also included. The FSW process-structure-fatigue performance relationships, including tool rotation, travel speeds, and pin tools are covered, along with sections on extreme fatigue conditions and environments, including multiaxial, variable

Fatigue Crack Growth in Integrally Stiffened Panels Joined Using Friction Stir Welding and Swept Friction Stir Spot Welding

Fatigue Crack Growth in Integrally Stiffened Panels Joined Using Friction Stir Welding and Swept Friction Stir Spot Welding
  • Author : Christian A. Widener,Dwight A. Burford,Bryan M. Tweedy
  • Publisher : Unknown Publisher
  • Release : 17 October 2021
GET THIS BOOKFatigue Crack Growth in Integrally Stiffened Panels Joined Using Friction Stir Welding and Swept Friction Stir Spot Welding

Fatigue crack growth rates in AA2024-T3 sheet joined to AA7075-T6 stiffeners by friction stir welding have been compared with rates measured in panels joined with rivets and in unstiffened parent material panels. Friction stir panels were prepared with both continuous friction stir welding (FSW) and swept friction stir spot welding (FSSW). Fatigue cracks in edge crack panels with continuous FSW joints tended to grow into the parent material away from the stiffeners. This behavior was attributed to the

Fatigue Behaviour of Aluminum Friction Stir Welds Under Highway Bridge Conditions

Fatigue Behaviour of Aluminum Friction Stir Welds Under Highway Bridge Conditions
  • Author : Shi Hui Guo
  • Publisher : Unknown Publisher
  • Release : 17 October 2021
GET THIS BOOKFatigue Behaviour of Aluminum Friction Stir Welds Under Highway Bridge Conditions

Friction stir welding (FSW) is a solid state joining process performed by rotating a cylindrical tool with a short protrusion between the two metal pieces to be joined. The combination of frictional and deformation heating leads to the consolidation of the joint. This welding method is rapidly growing in popularity in many applications, particularly in aluminum alloys for transportation vehicle (rail cars, ships) and bridge applications. Across North America, over 150,000 bridges have been identified as “structurally deficient” or “functionally obsolete”.

Mechanical, Metallurgical and Fatigue Properties of Friction Stir Welded and Tungsten Inert Gas Welded AA6061-T6 Aluminium Alloys

Mechanical, Metallurgical and Fatigue Properties of Friction Stir Welded and Tungsten Inert Gas Welded AA6061-T6 Aluminium Alloys
  • Author : Akshansh Mishra,A Razal Rose,Saravanan .M,Anand Singh
  • Publisher : GRIN Verlag
  • Release : 11 September 2017
GET THIS BOOKMechanical, Metallurgical and Fatigue Properties of Friction Stir Welded and Tungsten Inert Gas Welded AA6061-T6 Aluminium Alloys

Project Report from the year 2017 in the subject Engineering - Mechanical Engineering, grade: 8.9, SRM University, language: English, abstract: This paper deals with the mechanical, microstructural and fatigue analysis of welded joints. In the study, 6061-T6 aluminium alloy plates in 4mm thickness, that are particularly used for aerospace and in automotive industries, were welded using Tungsten Inert Gas (TIG) welding and Friction Stir Welding (FSW) methods as similar joints with one side pass and parameters of varying tool rotation, weld speed

Advances in Friction-Stir Welding and Processing

Advances in Friction-Stir Welding and Processing
  • Author : M.-K. Besharati-Givi,P. Asadi
  • Publisher : Elsevier
  • Release : 08 December 2014
GET THIS BOOKAdvances in Friction-Stir Welding and Processing

Friction-stir welding (FSW) is a solid-state joining process primarily used on aluminum, and is also widely used for joining dissimilar metals such as aluminum, magnesium, copper and ferrous alloys. Recently, a friction-stir processing (FSP) technique based on FSW has been used for microstructural modifications, the homogenized and refined microstructure along with the reduced porosity resulting in improved mechanical properties. Advances in friction-stir welding and processing deals with the processes involved in different metals and polymers, including their microstructural and mechanical

An Investigation Into Methods to Increase the Fatigue Life of Friction Stir Lap Welds

An Investigation Into Methods to Increase the Fatigue Life of Friction Stir Lap Welds
  • Author : Farzad Baratzadeh
  • Publisher : Unknown Publisher
  • Release : 17 October 2021
GET THIS BOOKAn Investigation Into Methods to Increase the Fatigue Life of Friction Stir Lap Welds

Recent advancements in friction stir welding (FSW) technology have potential for applications in aerospace structures. Friction stir spot welds have been found to be much stronger than rivets in the same material thickness, while maintaining the discontinuous crack growth path preferred by aircraft designers. In this study, the test coupons have been investigated in fatigue with the weld aligned with the loading direction. The purpose of this study was to better understand crack initiation at friction stir weld exit holes

Mechanical Fatigue of Metals

Mechanical Fatigue of Metals
  • Author : José A.F.O. Correia,Abílio M.P. De Jesus,António Augusto Fernandes,Rui Calçada
  • Publisher : Springer
  • Release : 07 May 2019
GET THIS BOOKMechanical Fatigue of Metals

This volume contains the proceedings of the XIX International Colloquium on Mechanical Fatigue of Metals, held at the Faculty of Engineering of the University of Porto, Portugal, 5-7 September 2018. This International Colloquium facilitated and encouraged the exchange of knowledge and experiences among the different communities involved in both basic and applied research in the field of the fatigue of metals, looking at the problem of fatigue exploring analytical and numerical simulative approaches. Fatigue damage represents one of the most important

Friction Stir Welding

Friction Stir Welding
  • Author : Daniela Lohwasser,Zhan Chen
  • Publisher : Elsevier
  • Release : 18 December 2009
GET THIS BOOKFriction Stir Welding

Friction stir welding (FSW) is a highly important and recently developed joining technology that produces a solid phase bond. It uses a rotating tool to generate frictional heat that causes material of the components to be welded to soften without reaching the melting point and allows the tool to move along the weld line. Plasticized material is transferred from the leading edge to trailing edge of the tool probe, leaving a solid phase bond between the two parts. Friction stir

Friction Stir Welding

Friction Stir Welding
  • Author : Noor Zaman Khan,Arshad Noor Siddiquee,Zahid Akhtar Khan
  • Publisher : CRC Press
  • Release : 28 July 2017
GET THIS BOOKFriction Stir Welding

The evolution of mechanical properties and its characterization is important to the weld quality whose further analysis requires mechanical property and microstructure correlation. Present book addresses the basic understanding of the Friction Stir Welding (FSW) process that includes effect of various process parameters on the quality of welded joints. It discusses about various problems related to the welding of dissimilar aluminium alloys including influence of FSW process parameters on the microstructure and mechanical properties of such alloys. As a case