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Fatigue and fracture toughness of electron beam welded joints of aluminum alloy 6156 (Al–Mg–Si) for aerospace applications
Author(s) -
Alexopoulos Nikolaos D.,
Examilioti Theano N.,
Stergiou Vasileios,
Kourkoulis Stavros K.
Publication year - 2021
Publication title -
fatigue and fracture of engineering materials and structures
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.887
H-Index - 84
eISSN - 1460-2695
pISSN - 8756-758X
DOI - 10.1111/ffe.13516
Subject(s) - materials science , welding , isothermal process , electron beam welding , fracture toughness , composite material , fracture (geology) , metallurgy , ultimate tensile strength , fatigue limit , alloy , cathode ray , electron , physics , quantum mechanics , thermodynamics
The mechanical behavior of AA6156 electron beam welded joints and the effect of artificial aging heat treatments on the fracture‐related properties were investigated. The fatigue test results of the welded joints presented lower fatigue endurance limit by approximately 60%, when compared to the base material. Fracture resistance results showed that the critical stress intensity factor ( K cr ) was essentially decreased (~32%) in the as‐welded condition. Heat treatment before welding presented a 15% increase in K cr for 4 h of artificial aging, while a decrease in K cr was noticed for prolonged isothermal heat treatment prior to welding. By applying post welding heat treatments, all investigated isothermal heat treatment conditions resulted in decreasing K cr . Tensile test results of the welded joints showed that an almost 40% increase of the yield stress can be achieved with appropriate post welding heat treatment, on the expense of only 10% decrease in K cr .