Cryogenic high purity aluminum (HPAL) conductor was originally developed and reported at the Air Force Research Laboratories in the 1980s. The basic idea was to exploit the potential to fabricate very high purity aluminum (5 or 6 ‘nines’ Al), which could achieve exceedingly low resistivity values in the 20 K and below temperature range. By using very high purity Al, the resistivity ratios...
To achieve Net Zero CO2 Emissions by 2050, aircraft industries are conducting extensive studies for future aircraft using new technologies such as hydrogen aircraft and electric aircraft. Since those new aircraft should carry liquid Hydrogen, its cryogenic temperature of 20K could be expected to be used as a coolant for the efficient fan motor and generator. Super-high-purity aluminum is a...
It is essential to develop lightweight cables with low AC loss in the application of electric aviation. High Purity Aluminum (HPAL), which operates effectively at cryogenic temperature, has been developed to compete with superconductors especially in higher frequencies. HPAL, characterized by 99.999% aluminum purity, achieves a residual resistivity ratio (RRR) up to 1000. It has minimum...
High power-density motors are required to meet demand for increasing interest in aircraft electrification. To reach these requirements high current density and lightweight conductors are required in the motor windings. With liquid cryogen on-board, low temperatures (20 K with LH2) are achievable where very high purity normal metals benefit from resistance ratio (RR) values of up to 1000. This...
