The effect of inert particles on grain structure development from alloy mel
t during laser rapid solidification has been investigated. It is found that
the presence of Al2O3 particles may disrupt the usual epitaxial grain stru
cture evolution of an aluminium 7075 alloy when processed by laser surface
remelting, This result, in addition to observations of crystal termination
at the particles and grain refinement in particle dense regions, indicates
that a mechanism of particle restricted grain growth operates. MST/4747.