1. Introduction
A heat source is utilized in thermal-spraying processes
to melt the feedstock. The molten or semi-molten material
is propelled toward a prepared substrate surface by
expansion of the process and atomization gases. The
subsequent impact of the in-flight particles on the substrate
generates a coating. Therefore, the efficiency of a
thermal-spraying process is dependent on the energy
consumed for melting the feedstock and the attained
deposition rate. The twin-wire arc-spraying (TWAS)
process is thus the most economical coating process
among the thermal-spraying techniques with respect to the
above mentioned reasons. In addition, by utilizing cored
wires, the TWAS process exhibits the highest variety in
feedstock. Coatings produced by means of TWAS show