Accession Number : AD0835051

Title :   300 C ROTATING RECTIFIER ALTERNATOR PHASE 1-B DIODE PROCUREMENT AND EVALUATION.

Descriptive Note : Technical rept. 15 May-15 Apr 68,

Corporate Author : WESTINGHOUSE ELECTRIC CORP LIMA OH AEROSPACE ELECTRICAL DIV

Personal Author(s) : Shilling, William J.

Report Date : JUN 1968

Pagination or Media Count : 107

Abstract : The purpose of this phase of the study, PHASE 1-B, was to procure a minimum of 15 more diodes and to test evaluate these diodes. While work was being done on PHASE 1-b, work was also accomplished on PHASE II consisting of completing the design of the alternator to the layout drawing. In PHASE 1-b silicon carbide rectifiers operable to 500 C have been prepared from grown junction crystals. These diodes operated at the contract requirements of 1.5A (half wave average) forward current at 100 volts (peak) reverse. A 'zero expension' encapsulation was designed and used for these diodes which incorporated pressure contacts to the diode. These pressure contacts solved the problem of cracking of the tungsten plate from the crystal due to differential expansion. Experiments designed to investigate the diffusion of nitrogen into p-type SiC were carried out. Although surface conversion was obtained, no rectifiers suitable for the contract were obtained by the diffusion method. Testing of grown junction diodes showed that they were suitable for a rotating application. The alternator design was completed to the layout drawing.

Descriptors :   (*SILICON CONTROLLED RECTIFIERS, PERFORMANCE(ENGINEERING)), CRYSTAL GROWTH, NITROGEN, SILICON CARBIDES, DIFFUSION, PRESSURE, CRACKS, TUNGSTEN, ROTATION, THERMAL STRESSES, SHOCK(MECHANICS), PROCUREMENT, MANUFACTURING, TEST SETS, TEST EQUIPMENT, VIBRATION, ENCAPSULATION, SALT SPRAY TESTS, ETHERS, VOLTAGE.

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE