Hardide Coatings Ltd, developer of Hardide surface coating technology, has recently completed raising funds for the construction of two additional reactors at the company’s U.S. facility. This comes shortly after Hardide gained National Aerospace and Defense Contractors Accreditation Program (Nadcap) accreditation for its Hardide-A coating.
The accreditation allowed Hardide to expand its business in the aerospace sector to offer advanced tungsten carbide-based coatings to aerospace manufacturers, which drove the decision to expand stateside operations. The accreditation followed its March 2017 award of approved supplier status by Airbus Group.
Aerospace is considered a key growth market for Hardide, according to Philip Kirkham, Hardide Coatings' CEO. “An increasing number of aerospace companies require their suppliers to be Nadcap accredited, so to be fully approved opens up the market to us. As well as cementing our position with customers such as Airbus, Leonardo, and BAE Systems, it will qualify us to work with any of the prime contractors and their worldwide supply chains.”
Hardide Coatings developed Hardide-A for the aerospace and defense industry as a replacement for toxic hard-chrome plating (HCP). HCP has been a mainstay of industrial coating in aerospace, heavy equipment, automotive, and various other industries where extreme operating environments require corrosion- and wear-resistant coatings. An example of this would be in hydraulic aircraft landing gear or wing flap actuators where leak-tight seals are present. Corroded metal finishes can accelerate seal degradation and affect reliability, downtime, and maintenance costs.
But the hexavalent chrome salts used to produce HCP pose extreme health and environmental hazards. HPC is to be banned shortly under European Union’s Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH) regulations.
Hardide-A has less environmental impact, possesses versatile geometric compatibility, corrosion and fatigue resistance. These are big advantages over alternatives like high- velocity oxygen fuel (HVOF) coating, cadmium plating, and other coating processes where spray coatings cannot be used.
Hardide-A requires minimal pre-coating part design changes and matches HCP in thickness and hardness. It has a low-friction, smooth-as-coated surface and can be diamond ground, honed, and superfinished for tighter dimensional accuracy. Hardide finishes also can survive impact and part deformation.
Overall, Hardide outperforms HCP and HVOF in terms off corrosion and fatigue resistance. In cases like the aircraft actuators, HVOF and other spray coatings can wear irregularly or leach cobalt binding agents while leaving tungsten carbide grains in place (which abrade seals). In abrasive or corrosive environments, the Hardide coating’s uniform nanostructure allows the coated part to wear uniformly and retain or even improve surface finish.
Although no potential Hardide customers had been pushing for Hardide Coatings to acquired Nadcap accreditation, the company—which secured a large order with General Electric in the second half of 2017—initiated the process three years ago.
“This accreditation really does prove that Hardide works under the most stringent process control standards required to coat aircraft components,” said Kirkham.