Specimens of Al-Fe 1–4 w/o, 2024 and 6061 Al have been surface melted with a pulsed Nd-glass laser. A TEM and SEM study showed that the dendrite spacings were from 2500 Å to 4000 Å which corresponds to a cooling rate of over 106 °C/sec. Melt depths obtained were in the range of 30–100 µm. No significant surface vaporization was observed at energy densities up to 440 J/cm2. Fracture surfaces of the commerical alloys demonstrated elongated porosity in the melt areas, probably due to internal hydrogen.
© 1978 Optical Society of America
L. S. Weinman, C. Kim, T. R. Tucker, and E. A. Metzbower, "Characteristics of laser surface melted aluminum alloys," Appl. Opt. 17, 906-910 (1978)