Enhanced Aluminum Conductor for Overhead Electrical Transmission Application

The DOE Conductivity-enhanced materials for Affordable, Breakthrough Leapfrog Electric and thermal applications (CABLE) initiative has brought together the insights of stakeholders in science & engineering, manufacturers, utility companies, and other entities in electrical product supply chains. These insights identified the need for new cost effective, conductivity-enhanced materials which will have a significant impact on the evolving national grid and electricity delivery system (EDS). Specifically, reducing transmission losses will be important for reducing costs to distributors and consumers. New materials will also play a significant role in the integration of renewable energy onto the grid. Recent events, such as the wildfires on the west coast of the United States, have also elucidated the need for increased component performance in extreme environments, where thermal stability, mechanical properties, and corrosion resistance may play a role in the operation and safety of the conductors. Material improvements to the components used for electrical transmission have been identified as a viable approach to implement a breakthrough solution at the fundamental level. These improvements will enable the concurrent design and development of more efficient, safer transmission cables to help meet the needs of the DOE. This thrust of the CABLE initiative also focuses on manufacturing and scale-up of new technologies to ensure that new materials can be fabricated at the lab scale in a way that is predictive of large-scale production. During the Phase I program, QuesTek Innovations, a leader in the field of Integrated Computational Materials Engineering (ICME) and 2016 Tibbetts Award recipient, applied its ICME-based Materials by Design® methodologies and designed three aluminum alloy concepts to achieve higher performance and value effectiveness in overhead electrical transmission applications. These alloy concepts were designed to achieve high electrical conductivity, withstand higher temperatures, improve strength over baseline materials, utilize novel strengthening phases while simultaneously being cost conscious, and demonstrating processibility and achieving target microstructures. During the Phase I program, the QuesTek team identified target property windows in % IACS and hardness and achieved them through alloying and material processing. Aging studies at elevated temperatures demonstrated greater thermal stability than incumbent aluminum alloys used in cables. Processing methods were identified for further investigation which would be conducive to industrial scale-up. Under the proposed Phase II effort, QuesTek will finalize the alloy design of the new aluminum conductor, considering a balance between performance and cost. The alloy will then be scaled-up with respect to material production to address the CABLE initiative thrust to capture at-volume relevant properties in laboratory/pilot scale production environments. QuesTek will develop a dataset relevant to cable applications and compare the new material with incumbent alloys, and work with OEMs to manufacture and test a demonstration component.