The Effect of Cu and Ge Additions on Strength and Precipitation in a lean 6xxx Aluminium Alloy

Electron Microscopy and Analysis Group Conference 2015

Mørtsell, E.A.^1 ; Marioara, C.D.^2 ; Andersen, S.J.^2 ; Røyset, J.^3 ; Reiso, O.^3 ; Holmestad, R.^1

Department of Physics, NTNU, Trondheim

7491, Norway^1

SINTEF Materials and Chemistry, Trondheim

N-7465, Norway^2

Hydro Aluminium RandD Sunndal, Sunndalsøra

N-6600, Norway^3

关键词: Al-Mg-Si alloys;    Disordered regions;    Ge addition;    Material hardness;    Nano-sized precipitates;    Precipitate size;    Precipitation process;    Strength loss;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/644/1/012028/pdf
DOI  :  10.1088/1742-6596/644/1/012028

来源: IOP

【 摘 要 】

It has been demonstrated that the strength loss in a lean Al-Mg-Si alloy due to solute reduction could be compensated by back-adding a lower at % of Ge and Cu. Nanosized precipitate needles which are the main cause of strength in these alloys, and material hardness has been correlated to parameters quantified by TEM. It was found that additions of Ge and Cu strongly affect the precipitation process by increasing precipitate density and reducing precipitate size. Investigations of precipitate atomic structure by HAADF-STEM indicated that they contain mixed areas of known phases and disordered regions. A hexagonal Si/Ge-network was found to be present in all precipitate cross sections.