The Chromefree 3rd quarter meeting was recently hosted by Weir Group at Strathclyde University. Our team gave a presentation alongside University of Leicester (UoL) and TWI. We presented our work so far; initial samples display an increase in hardness of the nickel deposit when SiC particles are co-deposited, and unsurprisingly, the nickel coatings prove to be tremendously corrosion resistant. TWI’s findings demonstrated that the coatings achieved a hardness of approximately 700HV, despite not yet being optimised.

As the project enters its 4th quarter, we will be focusing on optimisation within the 10-litre scale. The larger 50-litre tank has now been completed, and trials have begun to replicate the smaller bath. Once any issues have been fixed with regards to the 50 litre-bath, larger test pieces for JCB and other long-term wear and corrosion testing will take place.

It is still too early in the project to gauge the following: we do not know how well the coatings will perform in comparison to chrome plating, how easy or difficult on the ‘industrial scale’ it will be, or even how much the coatings will end up costing. Preliminary results are very positive, and we are confident that the process works. However, it is fair to argue that chrome plate will not be going anywhere anytime soon, even though there is still a large campaign to do so.

It is important to consider the limitations of chrome, specifically with regards to corrosion resistance. Nickel coatings could be extremely useful in environments such as offshore, where salt (chloride) readily attacks chrome plate, or within applications such as pumps for corrosive substances. In fact, this process could have a considerable advantage over many types of coatings – not just chrome plate.

It will be interesting to discover where Q4 takes us. The project has been extremely interesting and rewarding so far, and it is looking likely that our aim to find a hexavalent chrome free alternative to chrome plate could be achieved. 3 years ago, when the project first began, poor legislations and poorly conceived aims with little-to-no evidence created scaremongering and misinformation. Although it does seem that sense has now prevailed, at least in the medium term, chrome plate will not be disappearing for a while.

As a processor, TDC is largely customer-driven, and within the last few years several hexavalent chrome free alternatives have found their way into our process portfolio. None claim to outperform the hexavalent chrome processes they are replacing; in fact, many could be much lower in terms of capabilities. However, on this occasion, the drive generated could be beneficial, producing a suitable coating alternative. Design engineers who seek wear resistance and corrosion protection, without the use of hexavalent chrome, could benefit from our findings.