G Watkins, M A McMahon and W M Steen
surface treatment techniques, including laser surface
melting (LSM) and laser surface alloying (LSA) have been
the subject of considerable interest as a means of enhancing
the corrosion performance of aluminium and its alloys.
Microstructural modification together with the incorporation
of non-equilibrium concentrations of alloying elements
resulting from relatively rapid rates of cooling compared
with conventional surface treatment techniques provide
the basis for property enhancement. This paper considers
microstructural evolution in a range of laser surface
treated aluminium alloys including LSM of Al-Cu, Al-Si,
Al-Zn, Al-Fe and Al - transitional element alloy systems;
LSA of Al-Ni, Al-Cr and Al-Mo. Where reported, corrosion
and other property determination in these systems is discussed.
It is shown that surface alloys with unique microstructural
and compositional characteristics have been produced by
these techniques and that in many cases promising improvements
in hardness and critical pitting potential compared with
conventional alloys have been reported.