Kumar, G.S.V.; Heim, K.; Mukherjee, M.; Garcia-Moreno, F.; Banhart, J.: Investigation on the stabilization behaviour of MgAl2O4 (spinel) particles in aluminium foam via in-situ X-ray radioscopy and FIB tomography. Materials Today Communications 38 (2024), p. 108257/1-10
10.1016/j.mtcomm.2024.108257
Abstract:
The paper investigates the stabilization behaviour of in-situ created, sub-micron sized MgAl2O4 (spinel) particles at various concentration in Al-11 wt%Si foams. The foam evolution (expansion, coalescence and drainage) as a function of particle concentration and foaming time was monitored in-situ using X-ray radioscopy. The foam containing higher concentration (3.4 vol%) of MgAl2O4 exhibited higher stability and expansion until solidification. Decreasing the MgAl2O4 concentration to 2.5 vol% exhibited similar foam expansion like 3.4 vol% particle-containing foam, however the stability of the former is poor due to higher drainage. The foam containing lower MgAl2O4 concentration (1.7 vol%) showed poor stability and expansion due to further increase in drainage. The 3D visualisation of MgAl2O4 particles in the gas solid interface embedded in the oxide skin was brought out by FIB tomography. TEM analysis revealed that the nano-sized MgAl2O4 particles are closely embedded in the oxide skin.