TEMPERATURE AND RISE-TIME DEPENDENCE OF THE ELECTRIC STRENGTH OF ALKALI HALIDE CRYSTALS
Abstract
Techniques were developed to extend d-c and impulse breakdown measurements to liquid-helium temperature. The breakdown strength of KCl was measured from 4.2 to 425 K with d-c voltages and 1- and 10-microsec rise-time pulses. The temperature characteristic of the d-c electric strength reached a maximum of 1.16 Mv/cm at about 360 K and then dropped to 1.04 Mv/cm at 425 K. The breakdown strength was lower for d-c voltages than for pulses over the entire temperature range. For 1-microsec rise-time pulses, the maximum of the d-c temperature characteristic disappeared. Below 77 K, the breakdown strength measured with pulse and d-c voltages did not change appreciably. Changing the pulse rise time from one to ten microsec had little effect on electric strength. No thickness dependence was observed. The electric strength of a mixed crystal (75% KCl - 25% RbCl) was measured from 77 to 375 K. The temperature characteristic differed i shape from that of pure KCl; the slope at low temperatures was smaller and the maximum shifted to about 300 K. At 375 K, the breakdown strength of the mixed crystal had dropped to 0.60 Mv/cm.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1963
- Accession Number
- AD0403657
Entities
People
- Francis W. Kaseta
Organizations
- Massachusetts Institute of Technology