Interdiffusion between U(Mo,Pt) or U(Mo,Zr) and Al or Al A356 alloy

Solid state reactions in chemical diffusion couples U–7 wt.%Mo–0.9 wt.%Pt/Al at 580 °C and U–7 wt.%Mo–0.9 wt.%Pt/Al A356 alloy, U–7 wt.%Mo–1 wt.%Zr/Al and U–7 wt.%Mo–1 wt.%Zr/Al A356 alloy at 550 °C were characterized. Results were obtained from optical and scanning electron microscopy, electron probe microanalysis and X-ray diffraction. The UAl3, UAl4 and Al20Mo2U phases were identified in the interaction layers of γU(Mo,Pt)/Al and γU(Mo,Zr)/Al diffusion couples. Al43Mo4U6 ternary compound was also identified in γU(Mo,Zr)/Al due to the decomposition of γU(Mo,Zr) phase.The U(Al,Si)3 and U3Si5 phases were identified in the interaction layers of γU(Mo,Pt)/Al A356 and γU(Mo,Zr)/Al A356 diffusion couples. These phases are formed due to the migration of Si to the interaction layer. In the diffusion couple U(Mo,Zr)/Al A356, Zr5Al3 phase was also identified in the interaction layer.The use of synchrotron radiation at Brazilian Synchrotron Light Laboratory (LNLS, CNPq, Campinas, Brazil) was necessary to achieve a complete crystallographic characterization.