Premium
Fatigue behaviour of dissimilar Al 5052 and Mg AZ31 resistance spot welds with Sn‐coated steel interlayer
Author(s) -
Sun M,
Behravesh S B,
Wu L,
Zhou Y,
Jahed H
Publication year - 2017
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.12563
Subject(s) - materials science , spot welding , metallurgy , brittleness , fracture (geology) , aluminium , welding , alloy , composite material , fatigue limit , bending
The fatigue property of dissimilar spot welds between an aluminium alloy (AA5052) and a magnesium alloy (AZ31) was studied in this research. The AA5052 and AZ31 coupons were resistance spot welded together by using an interlayer of Sn‐coated steel between the two coupons. The fatigue test results revealed that the Mg/Al joints had the same level of fatigue strength as Mg/Mg resistance spot welds. It was found that within the life range of N f < 10 5 cycles, Mg/Al welds degraded faster than Mg/Mg joints. This was attributed to the larger bending moment on the plane of fatigue failure in the Mg/Al welds. Three failure modes were observed under different cyclic loading regimes: Al/steel interfacial failure, Mg coupon failure and Al coupon failure. Fatigue fracture surface of Mg/Al welds consisted of two distinct regions: crack propagation region with brittle morphology and final rupture with ductile morphology.