HREM, FIM and tomographic atom probe investigation of Guinier–Preston zones in an Al–1.54at% Cu alloy

Evaluation of strain caused by coherent precipitates in an Al alloy using TEM techniques

“…One of them is that the non-uniformity of the strain distribution can be attributed to microstructural factors that possibly occur at different rates near the precipitate-matrix interface, such as variations in the stoichiometry of the precipitate [16]. The explanation for this refers to the mode through which the elastic strains are "relieved" through the aging treatment.…”

“…The GP precipitate model consisted of a tetragonal lattice with two Cu planes separated by three Al planes with lattice parameters of 0.4049 × 0.4049 × 0.768 nm [16].…”

“…It was also observed that the separation distances between the precipitates were variable. It has been reported that the general form of GP precipitates is close to a rectangular prism with dimensions of 15× 15 ×1.5 nm [16]. Elastic strain caused by the difference between the precipitate and matrix lattice parameters, was measured in the surroundings of the precipitates specifically in the direction parallel to the dimension of 1.5 nm.…”

“…Because elastic strain values, caused by GP precipitates, are still controversial in the literature [16], this work presents a quantitative comparison of the results obtained by the DFH and HRTEM-GP techniques.…”

Identification of high temperature precipitation reactions in 2024 Al–Cu–Mg alloy through ultrasonic parameters

“…The effect of solution annealing temperature on the change of microstructural and mechanical properties of 2024 aluminium alloys was investigated using metallographic analysis, Vickers hardness measurements, and tensile tests [6]. Shollock et al [7] obtained the Al 3 Cu stoichiometry for 'h' phase, whereas Karlik et al [8] found a stoichiometry of Al 2 Cu. Different types of precipitation reactions in 2024 Al alloys were studied by X-ray diffraction and first principle calculations [9].…”