This article was published in ExtremeTech. The full text version can be found here.
By Graham Templeton
Electroplating has been around for quite some time, a well tested method of getting one metal onto another. Chrome plated engine exhausts, gold-plated jewelry, and rust-resistant industrial parts all rely on the process of using electricity to direct free-floating metal ions to attach to a larger source of metal. A new process from a startup called Modumetal has a fresh spin on this old classic however, laying down the coating metal in just such a way as to dramatically increase the strength of the final product.
The advance comes down the fact that, by slightly varying the properties of the electric field that directs the metal ions onto their target, Modumetal can control their exact pattern of attachment. More to the point, by varying that electric field over time they can create a layered coating, each layer designed to offset the weaknesses of the ones on either side of it. By depositing their coating layers in precise patterns, this technique can make it almost impossible for any single crack to work its way all the way through the coating, and greatly improve the metal’s physical properties.
This galvanized steel may be rust resistant, but it’s not a whole lot stronger.
This is called “nano-lamination” and technically applies to a proprietary alloy, but reports state that the technique can be applied to a variety of possible substrate metals. If nothing else, Modumetal sees their technique as a way to offset rust in long-term metal infrastructure, such as girders in subway stations. It’s not as though we lack avenues to rust-proof those materials now, of course, but if it adds enough life-time to infrastructure it could become a cost-effective solution for generalized super-weather-proofing.
But the coatings do confer protection against stronger chemical pressures than oxygen. Equipment used on oil rigs has to be able to shrug off very corrosive chemicals, often for years at a time, and again the layered structure of these metal coatings could dramatically slow the rate of equipment decay. They hope this will make unconventional sources of oil more desirable, as they won’t be breaking drills in highly acidic boreholes quite so often. This could have little more effect than change corporate balance sheets, but it could also change the incentive structure for the placement of new oil wells, potentially prompting oil companies to invest more heavily in drilling within first-world borders.
Unlike many advances in materials today, though, this just augments existing metals and building materials, rather than introducing a new one with truly superior qualities. As a result, applications are limited by the fact that they must build up the exterior of their targeted objects by as much as a centimeter. This means it won’t allow much miniaturization of parts, and likely won’t find its way into many parts of highly compact assemblies, like car engines.
Further, Modumetal claims that their technique is cost-comparable with other metal treatment techniques, such as galvanization. Galvanization, which is basically the addition of a zinc coating to the exterior of a metal, is often as simple as dipping the non-coated piece of metal in a bath of molten zinc — keeping it cost-comparable with that, especially for large-scale pieces, is quite a lofty goal to set. Modumetal says it wants to spark a “nanotech revolution,” and beating a major industrial process in both performance and price would definitely quiet the skeptics.