Speaker
Description
The development of ultrahigh power density rotating machines is a research priority identified by electric aircraft programs worldwide, including ARPA-E, NASA, Airbus, and many others. There are many high field DC and AC magnet applications of such wires. One of the most important building blocks for these applications is the electric wire conductors. A complete scan of the resistivity of these wires as a function of magnetic field and temperature is needed for a wide range of temperature from 5K to 150K, as machines are now being designed for these temperatures, e.g. cooled by liquid-H2, LN2, liquified-natural-gas (LNG), and even CO2 dry ice. This work will present the resistivity of electric wire conductors of interest, including 99.999+% Al hyperconductors, AlBe metal alloys, carbon-nanotube cables, and Al and Cu conductors with varying purity 99.5% to 99.99%, drawing tempers, and ultrafine diameters used in Litz cables. Properties are measured for a complete range of temperatures (2K to 300K) in increments of 2-10 K, and magnetic fields from 0-9T. A Quantum Design Physical Properties Measurement System (PPMS) is employed to obtain this data. Steps are taken to avoid heat generation during the measurement process. For ultrapure materials with very low resistance, longer time and repeated measurements were used to increase the signal-to-noise ratio.
Acknowledgments: Support by the Air Force Office of Scientific Research (AFOSR) LRIR # 18RQCOR100, and the Aerospace Systems Directorate (AFRL/RQ)
