X-Ray Study of G.P. Zones in Ternary Al–Zn–Mg Alloys

Abstract

X-ray diffuse scatterings at both small and high angles (111 Bragg angle) were measured with powder samples of Al-6.8 at%Zn base alloys containing 0.06 to 2.0 at%Mg.
In the alloys with low Mg concentrations the diffuse scattering around the 111 Bragg peak shows a size-effect scattering; the intensity becomes weaker with increasing Mg concentration and is scarecely observed beyond a certain Mg concentration. Such changes of scattering profiles with Mg concentration arise from the changes in static distortion around and inside a zone. The G.P. zones of the ternary alloys are discussed in view of this static distortion.