405 Crack growth and Fatigue Strength of Bent Aluminum Alloy under Plane Bending

The AA7050 aluminum alloy is widely used due to its low specific combined with high strength and toughness obtained from the heat treatment which involves solution treatment and ageing. It produces the mechanism of precipitation hardening of a thin phase and disperses. In this context, the present study to investigated three ageing treatments, their influence on fatigue crack growth. In order to find a better condition of precipitation of η' phase, which may increase resistance to fatigue crack growth of AA7050 aluminum alloy. The T614-65 condition was chosen as an alternative treatment in relation to T7451 and T6 conditions of current use in the industry. The fatigue crack growth rate results have shown that T614-65 fatigue strength were up to 14% higher than the shown for T7451 temper.

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Effect of Bending-Work on Fatigue Strength of Aluminum Alloy Plate under Out-of-Plane Bending

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.62.539 ◽

2013 ◽

Vol 62 (9) ◽

pp. 539-546 ◽

Cited By ~ 1

Author(s):

Kei OHKAWA ◽

Atsushi KUDO ◽

Takehiro ANDO ◽

Isao OHKAWA

Keyword(s):

Aluminum Alloy ◽

Fatigue Strength ◽

Alloy Plate ◽

Out Of Plane ◽

Aluminum Alloy Plate ◽

Plane Bending

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Fatigue Behavior and Fracture Mechanism of a Hot Rolled AA7020 Aluminum Alloy

International Journal of Current Engineering and Technology ◽

10.14741/ijcet/v.9.3.8 ◽

2019 ◽

Vol 9 (03) ◽

Cited By ~ 1

Author(s):

Ashish Thakur

Keyword(s):

Aluminum Alloy ◽

Fatigue Strength ◽

Crack Initiation ◽

Crack Growth ◽

Fracture Mechanism ◽

Fatigue Behavior ◽

Constant Load ◽

Fracture Mechanisms ◽

Hot Rolled ◽

Aa7020 Aluminum Alloy

Fatigue tests of smooth specimens and CT specimens of a hot rolled AA7020 Aluminum alloy have been performed in laboratory at ambient temperature. Fatigue strength and fatigue crack propagation (FCP) characteristic were evaluated and fracture mechanism was discussed on the basis of crack initiation, small crack growth, and fracture surface analysis. The growth behavior of small and large cracks has been investigated on 7020 alloy.The FCP resistance was found significantly lower than that of other aluminum alloys. The crack growth measurements were performed in CT specimens at constant load ratios ranging from R = 0.1–0.5. The fatigue strength at 104 cycles was 110 MPa that led to a considerably fatigue ratio of 0.1, fatigue failure did not occur. There existed two different modes of crack initiation depending on applied stress level. Above 200 MPa, cracks initiated at the specimen surface in transgranular or intergranular manner due to cyclic slip deformation, while below that stress subsurface crack initiation took place. The growth of small cracks initiated at the surface coincided with the FCP characteristic after allowing for crack closure for large cracks, but the operative fracture mechanisms were different between small and large cracks.

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