| 摘要 |
<p>The pointed end of a tungsten wire for use with a crystal detector is hardened by carbonishing. In one method the pointed end is brought into contact for a few seconds with a carbon block heated to 1500-1600 DEG C. in an inert atmosphere. In another method, the tip of the wire is brought into contact for a few seconds with a filament of tungsten at a temperature of 1500-2000 DEG C. arranged in a bell-jar through which is passed an atmosphere produced by bubbling a mixture of 80 per cent. nitrogen and 20 per cent. hydrogen through xylene at room temperature. Specification 577,181, [Group III], is referred to.</p> |
