Heat treatment of Al-Si-Cu-Mg casting alloys

ERRATA

Heat treatment of Al-Si-Cu-Mg casting alloys

EMMA SJÖLANDER

Department of Mechanical Engineering, Materials and Manufacturing – Casting SCHOOL OF ENGINEERING, JÖNKÖPING UNIVERSITY

Department of Materials and Manufacturing Technology CHALMERS UNIVERSITY OF TECHNOLOGY Section Page Errata

Kappa 31 See text below.

Kappa 32 The Taylor factor, M, is missing in eq. 12.

Suppl. V 18 Reference 8 should be 6 in Figure 19a.

Suppl. V 22 Reference 34 should be M. Vedani, E. Gariboldi, Acta Mater. 44 (1996) 3077-3088.

Suppl. VI 4-7 The notations ܥ

and ܥ

have the same meaning, i.e. concentration of alloying element X in the α-Al matrix.

௑ ௑

Suppl. VI 7 The Taylor factor, M, is missing in eq. 14.

The calculation of the reduced diffusion distance used in the solution treatment model is not correct.

This concerns Figure 16b on page 31 as well as associated papers: Supplement II Figure 5b on page S48 and Supplement III Figure 9b on page 15. A new calculation has been made. The microstructure of the Al-Si-Cu alloy consist of about 60 vol% Al-Si eutectic according to a mass balance calculation.

The Al-Si eutectic was given a diffusivity 5 times higher than for the primary α-Al phase in

accordance with the article by Wang et al. (Mater. Sci. Eng. A 425 (2006) 78-82). Different positions for the Al-Si eutectic relative the Al

Cu phase and the primary α-Al phase were investigated for the geometry of the model. The geometry in Figure 1a is in best agreement with the microstructure and is used for the analysis. The modelled increase in Cu concentration in the centre of dendrite arms during solution treatment for the Al-Si-Cu alloy is lower than the measured, see Figure 1b. The deviation is likely due to the too low initial concentration after solidification calculated using Scheil segregation.

Al

Cu

Al Al-Si

Al

0.0 1.0 2.0 3.0

wt % C u

Al-Si-Cu SDAS 10 µm SDAS 25 µm SDAS 50 µm model

2 s

Cu SHT

r D t

Figure 1 a) The spherical geometry used for the solution treatment model for the Al-Si-Cu alloy. b) Comparison between measured and modelled data.