TEM study of continuous precipitation in Mg-9 wt%Al-1 wt%Zn alloy[Transmission Electron Microscopy]

Journal Article · Thu May 11 04:00:00 EDT 2000 · Acta Materialia

DOI:https://doi.org/10.1016/S1359-6454(00)00004-5· OSTI ID:20075933

Celotto, S

The development of continuous precipitate morphology in heat-treated Mg-9 wt%Al-1 wt%Zn alloy (AZ91) for a range of ageing temperatures is investigated in detail using TEM. The matrix/precipitate orientation relationships (ORs), sizes, shapes and the number of precipitates per unit volume (N{sub V}) are described for ageing at temperatures from 70 to 300 C. Most of the continuous precipitates have a Burgers OR and are plate-shaped with the primary habit plane parallel to the basal plane of the matrix. These precipitates are initially lozenge-shaped plates that elongate with time at temperature to become long laths. Two other smaller populations of precipitates that have ORs different from the Burgers OR are also present. These precipitates are rod-shaped with their long direction either perpendicular to or inclined to the basal plane. The relationship between the continuous precipitate morphology and the hardness response is discussed and comparisons are made with high-strength aluminum alloys.

• Research Organization: CSIRO Manufacturing Science and Technology, Melbourne, Victoria (AU)
• OSTI ID: 20075933
• Journal Information: Acta Materialia, Journal Name: Acta Materialia Journal Issue: 8 Vol. 48; ISSN 1359-6454; ISSN ACMAFD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AGING
ALUMINIUM ALLOYS
HARDNESS
MAGNESIUM ALLOYS
MICROSTRUCTURE
PRECIPITATION
TEMPERATURE DEPENDENCE
TRANSMISSION ELECTRON MICROSCOPY
ZINC ALLOYS