Amorphous Chromium Carbide (a-CrC) Coating Deposited by Low Temperature Chemical Vapor Deposition for Corrosion and Wear Applications
October 25, 2023 3:45 pm
IBC Materials and Technologies has developed an innovative amorphous chromium carbide (a-CrC) coating, deposited via low-temperature chemical vapor deposition (CVD) technology. Unlike most other commercial CVD coatings that are deposited above 1000°C, a-CrC is applied at less than 450°C. This allows for the coating of most engineering materials without negatively affecting the mechanical properties or dimensional stability. The a-CrC coating bonds directly and tenaciously to a large variety of metals, including alloys of steel, stainless steel, nickel, titanium, molybdenum, tungsten, copper, magnesium, and aluminum, as well as ceramics and composites. With a hardness of over 1500 HV, a-CrC can provide a substantial improvement to wear, abrasion, and galling resistance. The amorphous, chemically inert microstructure of a-CrC is characterized by its complete lack of pores, grain boundaries, cracks, or other defects. The coating process is also non-line-of-sight, which ensures uniform coverage for complex components and tight tolerances. This combination of density and conformity leads to unmatched corrosion performance. Layers as thin as 2 microns can provide complete immunity against salt fog, concentrated acids, and crevice corrosion. Additionally, a-CrC is unaffected by high temperature oxidation up to 750°C. Unlike many metal plating or CVD coatings, the a-CrC process does not use or produce hazardous acidic waste or hexavalent chromium compounds. IBC has demonstrated the performance of this coating technology across several demanding Department of Defense (DoD) and commercial applications to date, including cadmium replacement, hard chrome replacement, liquid gallium corrosion resistance, and molten sodium corrosion resistance.