The variation with temperature of the magnetic leakage field in cobalt

The variation with temperature of the magnetic leakage field of an unmagnetized crystal of hexagonal cobalt has been investigated by means of an electron beam. Both the prism and hexagonal faces were examined in the temperature range of 20 to 380 °C by a new method using a divergent electron beam. In addition, the prism face was studied from 20 to — 170 °C. It was found that the strength of the magnetic leakage field decreased steadily with increasing temperature. It became negligible at about 260 °C and this condition persisted up to 380 °C. It was also found that the basic domain spacings did not change during heating or cooling of the crystal.