Controllable fabrication of micro-nano structure on Al-Li alloy by hydrothermal treatment

The micro-nano structures were successfully fabricated on Al-Li alloy by adjusting the concentration of sodium formate and controlling the hydrothermal temperature though hydrothermal treatment. The growing directions and morphologies for micro-nano structures were studied. The results show the micro-nano structures were a mixture of AlOOH and Al(OH) 3 with good crystallinity, the intensity of diffraction peaks increases with the increase of sodium formate concentration, and the growing direction of micro-nano structure varied from (2   0   0) at 110 °C and 130 °C to (1   1   1) at 150 °C. The morphologies of the micro-nano structures exhibit patterned surface with overlapping leaf-like nano-plates at 110 °C and 130 °C, nordstandite is predominant, flower-like at 150 °C,aluminum oxide hydroxide is predominant.These findings directly demonstrate that the preferential growing direction and the morphologies of micro-nano structure has been confirmed with the concentration of sodium formate and the hydrothermal temperature.