The copper alloys commonly referred to as nickel aluminum bronzes (NAB) are widely used in marine applications due to their excellent seawater corrosion resistance and good mechanical properties. Unfortunately, these alloys are susceptible to a variety of surface sensitive degradation processes such as cavitation and wear which significantly reduce service life. Laser surface melting and cladding techniques have recently demonstrated a potential to substantially enhance the performance of NAB components. This is associated with the occurrence of a martensitic or Widmanstätten transformation from the high temperature bcc β phase accompanied by precipitation of ordered intermetallic particles collectively referred to as κ. Optimization of these techniques requires an improved understanding of the evolution of microstructure in the NAB system under conditions of rapid solidification, however little data is currently available. In this paper, transmission electron microscopy is used to examine the microstructures of a series of laser surface melted NAB alloys containing from 8 to 12 wt. % Al, 3.8 to 6.5 wt. % Ni, 3.8 to 6.5 wt. % Fe, ∽1 wt. % Mn and, in some cases, lesser amounts of Ti or Zr.