Corrosion Behaviour of a SiOxNy Coated and Nitrided PH Stainless Steel

E. DALIBON; MAURO MOSCATELLI; L. ESCALADA; S. SIMISON; A. CABO; CARLOS LASORSA; S. BRÜHL

Procedia Materials Science

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2015 vol. 8 p. 29 - 38

2211-8128

Precipitation hardening stainless steels are used in applications where wear and corrosion resistance are required. To improve thesurface properties, thermochemical treatments in combination with hard coatings can be used.In this work, the corrosion behaviour of SiOxNy coatings deposited on nitrided and non-nitrided Corrax® PH stainless steel wereevaluated comparing them with the behaviour of samples which were only nitrided (two different conditions of nitrogenpercentage in the working gases were used).The microstructure was analyzed. Corrosion behaviour was evaluated by the Salt Spray Fog Test and cyclic potentiodynamicpolarization in NaCl solution. Erosion-corrosion tests were conducted.The thickness of the coating was about 1.4 microns, and its hardness was 2300 HV. The film had better erosion and corrosionbehaviour when it was deposited on the nitrided steel. This fact demonstrated that the nitrided layer results in a good interfacethat improves the adhesion and mechanical support