By controlling material interfaces at the nano-scale, Modumetal Inc. (Seattle, Wash.; www.modumetal.com) has developed a method for creating a new class of alloys with precisely defined properties through nanolamination. In this process, a part, such as a valve or fastener, is submerged in a tank containing various metal electrolytes. Through current-controlled electric-field modulation, metal ions are deposited onto the part in specific microstructures and layers. Unlike other electric-field-modulation processes, which are based on mass-transfer control, this process modulates the composition and structure of the alloy continuously. This level of control over the alloy’s properties at the interface between the original part and the deposited layer allows for customized parts to be “grown” — a process the company likens to biological activities, such as the growth of tree trunks.
The company touts corrosion resistance among the most desirable benefits of nanolamination. In partnership with various oil and gas companies, Modumetal has performed numerous demonstrations of specialized nanolaminated parts (including large-scale equipment, such as pumps and valves) in downhole and marine environments. In recently published field-test results, the zinc-based nanolaminated coatings showed unprecedented corrosion resistance when compared with traditional materials, including galvanized parts and those with cadmium-based coatings, all while maintaining strength and thickness requirements.
Last year, the company opened a full-scale production facility for its nanolaminated coatings in Snohomish County, Wash. Here, equipment and tubular components of many types are nanolaminated. Because the metals are grown using low-cost electrochemistry, Modumetal says the nanolamination process can operate with economics similar to traditional electroplating processes, even for large length scales of 12–20 ft. Additionally, smaller components like fasteners are processed with very high throughput. Modumetal currently works with both end users and equipment manufacturers to clad the materials. Going forward, Modumetal will continue working alongside industry leaders to deploy its nanolaminated coatings.