Water reaction characteristics of highly active aluminum-based alloy powder

In order to improve the reaction efficiency and rate of Al powder with seawater, highly active Al base powder (Al-Mg-Sn-Bi alloy powder, AMSB) was prepared by adding low melting metal (Sn and Bi) by atomizing. The hydrogen generation rate and open circuit potential of AMSB alloy powder were measured by hydrogen generation test and electrochemical test, and the hydrolysis mechanism was characterized. The hydrogen generation test results show that the hydrogen generation rate of AMSB alloy powder in 3.5%(mass fraction) NaCl solution can reach 214.80 mL·min-1·g-1, and the hydrogen generation efficiency can reach 80.45%. The results of electrochemical experiments show that the addition of Sn and Bi can reduce the open circuit potential of AMSB alloy powder and promote the negative shift of the electrode potential of Al powder. The phase composition and microstructure of AMSB alloy powder before and after the reaction were characterized by XRD, XPS and SEM-EDS. Low melting point elements Sn and Bi can destroy the densification of oxide film, effectively improve the reaction efficiency of Al with water and promote the reaction process of Al and water. Moreover, the galvanic cell effect formed between Al, Sn and Bi elements is an important reason for the improvement of the hydrolysis performance of AMSB alloy powder. Therefore, the highly active Al based powder prepared has a certain application value in the field of high energy water reaction metal fuel.