Abstract: High-power-density electron beam with single pulse was performed on the LD11R aluminum alloy. The electron beam was focused to three typical positions. For each case) the distribution of the solute concentration at the cavity bottom solid-liquid interface was investigated by using the "rapidly fixing" method. The interaction of the beam and solute atoms was analyzed. A new mechanism of explosive vaporization was proposed based on the present results. The occurrence of this explosive vaporization soiree was discussed.

Key words: electron beam, focus position, distribution of solute, explosive vaporization