Comparative corrosion studies of zirconia particle reinforced high‐alloyed 14‐6‐6 CrMnNi‐steel by potentiodynamic polarisation and one year outdoor exposure

Abstract

The corrosion behaviour of a spark plasma sintered CrMnNi high‐alloyed steel, without and with 10 vol.% zirconia particle reinforcement was investigated by potentiodynamic polarisation in 5 wt.% sodium chloride solution and by an one year outdoor exposure test. After the polarisation test both materials revealed a similar damage behaviour as in the outdoor exposure test. The unreinforced material was attacked by pitting corrosion, whereas the particle reinforced material showed a more homogeneous corrosion attack involving an intensified particle detachment. Furthermore, investigations of the unreinforced steel by white light interferometry revealed pit depths of approximately 65 µm after potentiodynamic polarisation and 36 µm after one year outdoor exposure. In contrast, for the composite a damage evolution due to particle detachment was found in both experiments.