Microstructural and compositional evolution of nanoporous silver during dealloying of rapidly solidified Mg65Ag35 alloy

• Nanoporous silver can be fabricated by chemical dealloying of Mg65Ag35 alloy.
• Residual Mg decreases with dealloying time following an exponential decay formula.
• Coarsening of NPS follows a nonlinear relationship with an exponent of ∼4.8.
• The activation energy is 55.7 ± 2.9 KJ mol−1 for the chemical dealloying of Mg65Ag35.

Microstructural and compositional evolution of nanoporous silver (NPS) during dealloying of rapidly solidified Mg65Ag35 alloy in the 1 wt% HCl solution has been investigated using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray analysis. The amount of MgAg phase decreases and that of f.c.c. Ag increases with increasing dealloying time, and no intermediate phase occurs during dealloying. The residual Mg content in NPS decreases with increasing dealloying time, following an exponential decay formula. The coarsening of ligaments in NPS with dealloying time follows a nonlinear relationship, and the coarsening exponent (n) is ∼4.8 for the dealloying of Mg65Ag35. In addition, the activation energy is 55.7 ± 2.9 kJ mol−1 for the chemical dealloying of the rapidly solidified Mg65Ag35 alloy in the HCl solution.