| 摘要 |
<p>Ferrite material for use at VHF and cryogenic temps. comprises in mol. % 26.3-31 Fe2O3, 50.8-54 CaO, 9.3-31.1 V2O5 and 1.8-13.6 TiO2. It is prepd. by (a) firing 4 hrs at 1000-1020 degrees C, (b) 4 hrs at 1050-1070 degrees C, and (c) 20 hrs at 1170-1200 degrees C, in an oxidising atmosphere, being cooled and crushed between each stage. The material has a relatively low satn. magnetisation and a sufficiently restricted resonance range at cryogenic temps. for efficient use.</p> |
