Deposition of Multicomponent Chromium Carbide Coatings Using a Non-Conventional Source of Chromium and Silicon with Micro-Additions of Boron

Abstract

The chromium carbide coatings are widely used in the mechanical industry due to its corrosion resistance and mechanical properties. In this work, we evaluated a new source of chromium and silicon with micro-additions of boron on the deposition of multi-component coatings of chromium carbides in W108 steel. The coatings were obtained by the pack cementation method, using a simultaneous deposition at 1000 oC for 4h. The coatings were analyzed by X-ray diffraction, X-ray energy dispersive spectroscopy, optical microscopy, microhardness test method and pin-on-disc wear test. It was found that the coatings formed on W108 steel were mainly constituted by (Cr,Fe)23C6, (Cr,Fe)7C3, Cr5-xSi3-xCx+z, Cr3B0,44C1,4 and (or) Cr7BC4. The carbide layers showed thicknesses between 14 and 15 µm and maximum values of microhardness between 15.8 and 18.8 GPa. Also, the micro-additions of boron to the mixtures showed statistically significant influence on the thickness, microhardness and abrasive wear resistance of the carbide coatings.

Keywords

• Chrome-boronizing-siliconizing
• chromizing
• chromium carbide
• multicomponent coating
• chromite
• pack cementation method