Fig. 48 Hardness curve for an Al-4Cu alloy showing the relationship between the various precipitates formed and the hardness on aging at 130 °C (265 °F). Compare this curve to the structures shown in Fig. 46 . GP, Guinier-Preston. Source: Ref 17 More

Fig. 49 Hardness as a function of aging time for an Al-4Cu alloy. The alloy was solution annealed for at least 48 h at 520 °C (970 °F), then cooled quickly (water quenched) to 25 °C (77 °F). Adapted from Ref 38 More

Fig. 26 Correlation of structure and hardness of Al-4Cu alloy aged at two different temperatures. GP, Guinier-Preston. Source: Ref 75 More

Fig. 13 θ″ (GP-II) precipitates in aluminum-copper alloys. Al-4Cu alloy artificially aged for 8 h at 165 °C (330 °F), as seen by atom probe tomography. Dots are copper atoms; aluminum atoms are invisible. The regions of increased copper concentration are θ″ (GP-II). Courtesy of A. Biswas More

Fig. 14 Hardness evolution during artificial aging of different Al-4Cu alloys at two temperatures. The different line types mark the occurrence of Guinier-Preston (GP) zones and θ″ and θ′ phases. Adapted from Ref 111 More

Fig. 16 θ′ precipitates in Al-4Cu alloy. (a) Bright-field transmission electron microscopy image after artificial aging for 1 h at 190 °C (375 °F). The alloy contained 0.01 wt% Sn, which forms the spherical nucleation sites marked by arrows ( Ref 146 ). (b) Atom probe tomography of a volume 78 More

Fig. 13 Simulation of equiaxed solidification of Al-4Cu (wt%) alloy showing grain-boundary formation. Lapse time: (a) 0.04 s, (b) 0.08 s, (c) 0.16 s, (d) 0.2 s. Source: Ref 22 More

Fig. 16 Section through a bar of aged Al-4Cu alloy showing a crack initiated by fretting fatigue. Courtesy of R.B. Waterhouse, University of Nottingham More

Fig. 33 Cyclic deformation curves of polycrystalline Al-4Cu in different conditions. (a) θ″. (b) Fine θ′. (c) Coarse θ′. Source: Ref 176 , 177 , 178 More

Fig. 14 Compression strength of a series of Al-12Si and Zn-4Cu alloys. Test specimens were 30 × 30 × 40 mm (1.2 ×1.2 × 1.6 in.). Testing was performed at 5 mm/min (0.2 in./min). Because the transition from the initial linear increase of stress to the plateau regime is not defined unambiguously More

Fig. 13 Compression strength of a series of Al-12Si (open circles) and Zn-4Cu (solid circles) alloys. Test specimens were 30 by 30 by 40 mm (1.2 by 1.2 by 1.6 in.). Testing was performed at 5 mm/min (0.2 in./min). Because the transition from the initial linear increase of stress to the plateau More

Fig. 11 Comparisons of multiscale simulations of pore morphology with three wedge casting experiments. (a), (b), and (c) are x-ray tomography images of pores in Al-4Cu, Al-7Si, and Al-7.5Si-3.5Cu, respectively. (d), (e), and (f) are simulated pores in these three alloys. Source: Ref 68 More

Fig. 2 Relationship between strength and precipitate formation during aging of an Al-4Cu alloy. Source: Ref 7 More

Fig. 23 Predicted evolution of grain density during equiaxed dendritic solidification of Al-4Cu (wt%) alloy with grain movement inside 5 × 10 cm rectangular cavity cooled from left sidewall. Source: Ref 38 More

Fig. 24 Bright-field transmission electron microscopy image in the ⟨110⟩ α direction of Al-4Cu-0.1Mg-0.62Ag alloy aged for 1000 h at 250 °C (480 °F). It features Ω and θ′ precipitates. Source: Ref 174 More

Fig. 24 Effect of grain movement and different nucleation rates on predicted macrosegregation patterns in equiaxed dendritic solidification of Al-4Cu (wt%) alloy with grain movement inside 5 × 10 cm rectangular cavity cooled from left sidewall. Source: Ref 38 More

Fig. 10 GP-I zone in aluminum-copper alloys. High-resolution transmission electron microscopy image of a monolayer Guinier-Preston (GP) zone sheared by an edge dislocation in Al-4Cu alloy aged for 10 h at 100 °C (210 °F), including schematic of the event. Source: Ref 94 . Reprinted More

Fig. 15 High-angle annular dark-field transmission electron microscopy image along the ⟨001⟩ α direction showing θ′ precipitates and monolayer Guinier-Preston (GP)-I zones in Al-4Cu-0.05Sn alloy subjected to interrupted aging for 10 min at 200 °C (390 °F), followed by 30 days at 65 °C (150 °F More