TY - JOUR

T1 - Effect of filler materials on the tensile properties and fracture toughness of laser beam welded AA2198 joints under different ageing conditions

AU - Examilioti, Theano N.

AU - Karanikolas, Dimitris

AU - Riekehr, Stefan

AU - Al-Hamdany, Nowfal

AU - Papanikos, Paraskevas

AU - Klusemann, Benjamin

AU - Kashaev, Nikolai

AU - Alexopoulos, Nikolaos D.

N1 - Publisher Copyright: © 2023 Elsevier Ltd

PY - 2024/1/23

Y1 - 2024/1/23

N2 - The influence of different filler materials on the microstructure, tensile mechanical properties, and fracture toughness of laser beam welded AA2198 alloy as well as the effect of different artificial ageing heat treatments were investigated in this contribution. The welded joints were produced when exploited either, Al-Si (AA4047) or Al-Cu (AA2319) filler wires. It was shown that the Al-Si filler wire gave higher hardness values in the fusion zone when compared to the Al-Cu filler wire. The post heat treatment of the welded specimens increased by approximately +100 % the yield stress and by +20 % the ultimate tensile strength with increasing ageing time, in a similar way to the non-welded material. Elongation at fracture decreased in an inverse proportional manner to yield stress. Artificial ageing before welding gave improved elongation at fracture for the over-aged condition only. The quality index concept showed that the artificial ageing before the welding did not succeed in giving a higher quality of the welded joints, for both filler materials investigated. The opposite was shown on the post heat treatment, where the peak-aged condition increased substantially the ‘quality’ of the welded joints with both filler materials. The critical stress intensity factor was increased by +25 % for the under-aged condition for the post-welded condition and both investigated filler wires as a result of the balance between medium values in strength and ductility, respectively.

AB - The influence of different filler materials on the microstructure, tensile mechanical properties, and fracture toughness of laser beam welded AA2198 alloy as well as the effect of different artificial ageing heat treatments were investigated in this contribution. The welded joints were produced when exploited either, Al-Si (AA4047) or Al-Cu (AA2319) filler wires. It was shown that the Al-Si filler wire gave higher hardness values in the fusion zone when compared to the Al-Cu filler wire. The post heat treatment of the welded specimens increased by approximately +100 % the yield stress and by +20 % the ultimate tensile strength with increasing ageing time, in a similar way to the non-welded material. Elongation at fracture decreased in an inverse proportional manner to yield stress. Artificial ageing before welding gave improved elongation at fracture for the over-aged condition only. The quality index concept showed that the artificial ageing before the welding did not succeed in giving a higher quality of the welded joints, for both filler materials investigated. The opposite was shown on the post heat treatment, where the peak-aged condition increased substantially the ‘quality’ of the welded joints with both filler materials. The critical stress intensity factor was increased by +25 % for the under-aged condition for the post-welded condition and both investigated filler wires as a result of the balance between medium values in strength and ductility, respectively.

KW - Al-Li alloy

KW - Laser beam-welding

KW - Heat-treatment

KW - Mechanical properties

KW - Fracture toughness

KW - Microhardness

KW - Microstructure

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=85181130714&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/3677a49a-50da-3215-86c9-eda82dfd31e4/

U2 - 10.1016/j.engfracmech.2023.109811

DO - 10.1016/j.engfracmech.2023.109811

M3 - Journal articles

VL - 295

JO - Engineering Fracture Mechanics

JF - Engineering Fracture Mechanics

SN - 0013-7944

M1 - 109811

ER -