Optimisation of the electric wire arc-spraying process for improved wear resistance of sugar mill roller shells

A parametric study using Taguchi's fractional-factorial design L9 (34–2) was conducted to optimise the parameters of an electric wire arc spray process to develop coating for improved wear resistance of sugar mill rollers using an iron based material, iron–chromium–boron (FeCrB). Four spray parameters; current, voltage, air pressure and spray distance were evaluated using the Taguchi design. The coatings were characterised by their hardness, micro-structure and abrasive wear. The results of the study indicated that an optimum wear rate could be achieved from the relationships that exist between all parameters evaluated while achieving satisfactory hardness. The present Taguchi analysis employed in this investigation led to the optimised process parameters for the iron–chromium–boron coating with the lowest mass loss over a two-hour period. The coating should be a good candidate for application to sugar mill rollers.