Fig. 9 Fatigue fracture in aluminum alloy 2024-T3 tested first in vacuum (region A) and then in air (region B) (7500×). The arrow at the lower right indicates the direction of crack propagation. Note the flat, featureless fracture surface formed while testing in vacuum (region More

Fig. 9.15 Effects of T3 and T4 heat treatments on 2024 Al. YS, yield strength; UTS, ultimate tensile strength. Source: Ref 2 More

Fig. 26.4 Effect of heat treatment on 2024 and 7075. YS, yield strength; UTS, ultimate tensile strength. Source: Ref 7 More

Fig. 4.29 Extension of data for 2024-T4 to include compressive mean stresses (original data from Ref 4.17 ). (a) Fatigue life as a parameter. (b) Stress amplitude as a parameter More

Fig. 10.28 Fatigue crack initiation at a surface inclusion in 2024-T4 aluminum after 5% of total fatigue life. Source: Ref 10.24 More

Fig. 7 Crevice corrosion of an anodized aluminum alloy 2024-T851 window frame from the space shuttle Challenger . Corrosion occurred along both thermal and environmental sealing grooves. (a) Window frame showing locations of corrosion (arrows). (b) Enlargement of (a) showing corrosion More

Fig. 10 Example of exfoliation corrosion. (a) Failed alloy 2024-T4 tailplane fitting. Arrow points to corrosion that was produced by direct contact between a cadmium-plated steel bolt and the aluminum fitting. (b) Exfoliation in the tailplane fitting. 55× More

Fig. 12 Corrosion of an aluminum alloy 2024 helicopter rotor blade. (a) Leading edge at the blade tip showing three areas of severe corrosion. (b) Corrosion in the aluminum alloy skin at area 1. (c) Rupture of the surface skin at area 3 due to buildup of corrosion products in the underlying More

Fig. 27 Top view (a) of cracked aluminum alloy 2024-T351 pitostatic connectors. Arrows indicate cracks. (b) Cross section of one connector showing elongated grains that were cut to form connector threads. 25 x . (c) Cross section showing intergranular cracking with multiple branching in one More

Fig. 9 Forest Products Laboratory (FPL) 2024 aluminum surface. (a) High-resolution stereo electron micrograph. (b) Isometric drawing More

Fig. 10 Phosphoric acid anodization (PAA) 2024 aluminum surface. (a) Stereo micrograph. (b) Isometric drawing More

Fig. 11 Corrosion of alclad 2024-T3 adhesive-bonded panels (opened to show corrosion products) after exposure to 4480 h salt spray test More

Fig. 7 Alloy 2024-T3 sheet clad with alloy 1230 (5% per side), solution heat treated. Normal amount of copper and magnesium diffusion from base metal into cladding (top). Keller’s reagent. 100× More

Fig. 2.65 Tensile stress-strain curve for a 2024-T351 aluminum alloy plate. Source: Ref 2.39 More

Fig. 4.46 Crack growth behavior of 2024-T3 aluminum sheet. Source: Ref 4.52 More

Fig. 4.47 R -curve for the 2024-T3 aluminum sheet. “Guided” refers to use of a buckling guide. Source: Ref 4.52 More

Fig. 4.54 Effect of panel width on fracture toughness for bare 2024-T3 sheets. Source: Ref 4.10 More

Fig. 27 Aluminum alloys 2124 and 7475 are tougher versions of alloys 2024 and 7075. High-purity metal (low iron and silicon) and special processing techniques are needed to optimize toughness in these materials. Source: Ref 13 More

Fig. 29 Variation in rotating beam fatigue for (a) 2024-T4, (b) 7075-T6, (c) 2014-T6, and (d) 7079-T6 alloys. Notches (60°) were very sharp ( K t > 12), with a radius of approximately 0.005 mm (0.0002 in.). Results are from over a thousand rotating beam tests performed in the 1940s More

Fig. 30 Comparison of fatigue strength bands for 2014-T6, 2024-T4, and 7075-T6 aluminum alloys for rotating beam tests. Source: Ref 16 More