AeroMask: Development of masking for REACH-compliant Hardide CVD W/WC coating to replace Hard Chrome plating on 3D shapes and thin wall aerospace components

Hardide Coatings is developing a new masking compound that will allow its tungsten carbide coating to be applied selectively to complex aerospace parts, replacing the toxic hard chrome plating currently used. The problem is straightforward: Hardide’s coating is deposited through chemical vapour deposition (CVD), a non-line-of-sight process that coats every surface it reaches. To coat only specific areas of a 3D component—such as a thin-walled turbine blade or a fuel nozzle—the rest must be masked. But no commercial masking compound can withstand the high temperatures and reactive chemistry of the CVD process. The only current option is hard metal masking, which is slow, expensive, and often ineffective on intricate geometries. If the new masking compound works, aerospace manufacturers could switch from hard chrome plating—a process restricted under EU REACH regulations due to its toxicity—to a durable, wear-resistant tungsten carbide coating without redesigning their parts. The impact would be felt across the supply chain: faster production, fewer rejected components, and a cleaner manufacturing process for critical engine and landing-gear parts that must withstand extreme conditions.