Reactivity of Zircaloy-4 with Ti3SiC2 and Ti2AlC in the 1100-1300 °C temperature range

Herein, we report on the interactions between zirconium, in the form of Zircaloy-4 (Zr-4) and the MAX phases, Ti3SiC2 and Ti2AlC in the 1100-1300 °C range. In both cases, the A-group element, Al or Si, diffused out of the MAX phases and formed intermetallics with the Zr-4. Under comparable conditions, Si penetration into the Zr-4 was roughly an order of magnitude less than that of the Al from the Ti2AlC. The effective diffusion coefficient of Si can be described by Deff_Sim2s=7.4×10-9exp-170kJ/molRT; that of Al by Deff_Alm2s=9.3×10-12exp-38kJ/molRT. At 38 kJ/mol, the activation energy for the Ti2AlC/Zr-4 diffusion bonding process was significantly lower than that of the Ti3SiC2/Zr-4 diffusion couples, at 170 kJ/mol.