2000°F POWER WIRE FOR AEROSPACE ENVIRONMENT

摘要

The 22-gauge power-wire systems were found to have defective alumina end seals. The expansion joints in the end-seal design were found to be filled with braze material. This caused cracking of the end seal when the system was heated because of the large difference in coefficients of expansion of rhodium and alumina. A new end-seal design has been made which places the alumina in compression. Twelve-gauge Du Pont TD (thoria-dispersed) nickel had resistivities of 7.84 and 44.36 microhm-cm at 77 and 1400 F respectively.