Analysis of the mechanism of fatigue failure of the Refill Friction Stir Spot Welded overlap joints

• Autorzy: Kubit Andrzej , Trzepiecinski Tomasz , Bochnowski Wojciech , Drabczyk Mateusz , Faes Koen

Identyfikatory

DOI

10.1016/j.acme.2019.09.004

• Języki publikacji: EN

Abstrakty

EN

The aim of this work is the experimental investigation of fatigue failure in Refill Friction Stir Spot Welding joints. The specimens for the fatigue analysis were made of 0.8-mm-thick and 1.6-mm-thick 7075-T6 aluminium alloy which is used to fabricate aircraft fuselages con-sisting of a plate skin with a stiffening stringer. The load capacity of joints was determined by tensile/shear tests. Fatigue tests were carried out on an Instron E10000 testing machine at room temperature. High-cycle fatigue tests were carried out under the following conditions: a limited number of cycles equal to 2 _ 106, a frequency of 50 (Hz), and a coefficient of stress cycle R = 0.1. Microstructural features of fatigue fractures for different levels of variable load were examined using Scanning Electron Microscopy micrographs. The analysis of the fatigue fractures reveals that the Alclad layer at the bottom of the weld is a kind of structural notch and in this situation can be the location of the initiation of fatigue cracking. It was found that fracture mechanism depends on the value of load amplitude. Analysis of the SEM micrographs of fatigue fractures shown that the thermo-mechanically affected zone and heat affected zone are sources of fatigue failure.

Słowa kluczowe

EN

aircraft engineering; aluminium alloys; fatigue strength; high-cycle fatigue; welded joints

PL

inżynieria lotnicza; stopy aluminium; siła zmęczeniowa; zmęczenie wysokocyklowe; połączenia spawane

• Wydawca: Springer ; Wrocław University of Science and Technology
• Czasopismo: Archives of Civil and Mechanical Engineering
• Rocznik: 2019
• Tom: Vol. 19, no. 4
• Strony: 1419--1430
• Opis fizyczny: Bibliogr. 27 poz., rys., wykr.

Twórcy

autor

Kubit Andrzej

• Department of Manufacturing and Production Engineering, Rzeszow University of Technology, 8 Powst. Warszawy Ave., 35-959 Rzeszów, Poland

autor

Trzepiecinski Tomasz

• bDepartment of Materials Forming and Processing, Rzeszow University of Technology, 8 Powst. Warszawy Ave., 35-959 Rzeszów, Poland

autor

Bochnowski Wojciech

• Department of Mathematics and Natural Sciences, University of Rzeszow, 1 Pigonia St., 35-310 Rzeszów, Poland

autor

Drabczyk Mateusz

• Department of Mechanics and Mechanical Engineering, University of Rzeszow, 1 Pigonia St., 35-310 Rzeszów, Poland

autor

Faes Koen

• Belgian Welding Institute, Technologiepark-Zwijnaarde 935, 9052 Gent, Belgium

Bibliografia

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Uwagi

PL

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020)