Measurement of thermodiffusion in liquid Ag60Cu40

Kurzfassung

Thermodiffusion, or the Soret effect, designates a diffusive motion of particles driven by a temperature gradient, leading to a build-up of a concentration gradient. This effect is here measured in the liquid state on the eutectic alloy Ag60Cu40, which shows negligible excess volume. No significant thermodiffusion was observed using both in situ X-ray radiography or ex situ energy-dispersive X-ray spectroscopy on separately solidified parts of the sample. This is in contrast to the significant Soret coefficients observed in molten Ag-Al and Al-Ni. Molecular dynamics simulations of thermodiffusion in liquid Ag-Cu [Sarder et al., Philos. Mag. 99, 468–491 (2019)] report significantly stronger thermodiffusion. However, the trend that thermodiffusion in liquid Ag-Cu is weaker than in other liquid alloys like Al-Ni is supported by our experiment.