Original scientific paper
X-ray diffraction study of discontinuous precipitation in Al-Cu alloys
S. Popović
; Institute "Ruđer Bošković", Zagreb
Abstract
The discontinuous precipitation process of equilibrium ⦻ phase in Al-Cu alloys is studied by X-ray diffraction method using powdered samples. When the process takes place each matrix diffraction line splits into two components differing slightly in unit cell dimensions. The component with the smaller unit cell dimension corresponds to the as-quenched alloy, the other component corresponds to the slowly-cooled alloy. Proceeding the ageing time the former component gradually transforms into the latter. This transformation can be studied following the changes of the profiles of matrix diffraction lines at high Bragg angles. The ageing times, giving similar volume fractions having undergone the discontinuous precipitation process at two different temperatures, were determined An activation energy for solute atom diffusion of 1.1 eV is obtained.
Keywords
X-ray diffraction; Al-Cu alloys
Hrčak ID:
321422
URI
Publication date:
1.11.1970.
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