Cd, Cr Alternatives

Many organizations, especially in aerospace and defense, are looking for alternatives to hard chrome plating to reduce pollution and improve performance. This is being given more impetus by the fact that chromic acid has now been put forward for REACH Annex XIV, which will ultimately lead to the loss of chrome plating in Europe.

  • HCAT and C-HCAT – Rowan Technology Group and Bruce Sartwell, of NRL, ran the Hard Chrome Alternatives Team (HCAT), which did the evaluation work that formed the basis for approving HVOF WC-CoCr and WC-Co for aerospace landing gear and other components. Rowan was the data manager and coordinator for the Canadian HCAT (C-HCAT), maintaining coordination between the U.S. and Canadian teams and integrating the Canadian data on chrome replacement. As a result of these programs HVOF technology has now replaced hard chrome on all new design commercial and military landing gear and many actuators and other components.
  • Advanced Surface Engineering Technologies for a Sustainable Defense – Rowan is the Technical Manager for ASETSDefense, a DoD initiative sponsored by Strategic Environmental Research and Development Program (SERDP) and Environmental Security Technology Certification Program (ESTCP). The objective of ASETSDefense is to facilitate the implementation of new, environmentally friendly technologies for coatings and surface treatments by providing ready access to background information and technical data from research, development, test, and evaluation efforts as well as the status of approvals and implementations. ASETSDefense provides users with information and assistance to improve weapons system performance and life-cycle cost while reducing or eliminating environmental safety and occupational health (ESOH) impacts from coatings and treatment processes that utilize hexavalent chromium (hex chrome, Cr6+, Cr(VI), chromate, chromic acid), cadmium, beryllium, and VOCs. ASETSDefense organizes and runs highly regarded workshops and maintains a database of technical data, authorizations and implementations of alternatives. Most of this data is available to the public.
  • Chrome Alternatives for Internal Diameters – Rowan aided the evaluation of several alternatives for ID chrome replacement, including plasma spray. The better option was a new nanophase Co-P coating from Integran in Canada. This coating has now been developed and is in qualification at Jacksonville Naval Aviation Depot.
  • Chrome and Cadmium Avoidance on the Joint Strike Fighter – Rowan has been involved in the JSF program for some years, and has carried out several technology analyses of chrome alternatives for outer and inner diameters and has produced an extensive data compilation to assist engineers in adapting alternatives.
  • Canadian Markets for HVOF as a Chrome Replacement – The report for Industry Canada assessed the potential market sizes and characteristics for chrome replacement in the Canadian transportation, oil and gas, forestry, and machinery sectors.
  • Assistance to NRC in establishing coating initiatives – The National Research Council of Canada contracted with Rowan to assist in developing market strategies, collaboration, and teaming with Canadian and US partners in various coating programs.   This assistance included work with the Canadian Cadmium Replacement Program.
  • Cadmium Alternatives – Cadmium has been replaced in the automotive and electronics industries as a result of the European ELV, WEE and RoHS directives, but it is still used in aerospace and defense. The replacement issues are very complex, and Rowan keeps track of the options and assists DoD and aerospace and electronics companies with adopting alternatives such as electroplated LHE ZnNi, electroplated Al, and dip-spin polymers, each of which has applications in the industry.
  • Coatings to Replace Hard Chrome on Hydraulics – These are two very different problems with very different solutions. Rowan is helping a hydraulics manufacturing company to adopt a high energy plasma spray technology to replace hard chrome. The work involves testing different coating powders for best performance and efficiency, hydraulic testing, evaluation of environmental and health issues, specification of process and equipment, qualification and training.
  • Coatings to Replace Hard Chrome on Mill Rolls – Mill rolls are a very different problem. The solution is not usually thermal spray, since it is too expensive. The problem with REACH, however, is that the materials for almost all wear-resistant plating alternatives are being restricted at the same time, leaving European industry with no cost-effective alternatives.