| 摘要 |
PURPOSE:To prepare the titled crucible without growing crystal granules in preparing a single crystal on the surface of the crucible, by drawing a thin sheet of Pt (or Pt-Rh alloy) while heat-treating the thin sheet in the course of the drawing. CONSTITUTION:A Pt sheet having about 2mm. thickness is drawn, e.g. by the stretch press drawing or plate drawing, while heat-treated at about 900 deg.C or below a suitable number of times in the course of drawing to form a crucible having about 180mm. height, about 160mm. length in the straight cylinder part, about 70 degrees tilting angle at the V-shaped bottom, about 40mm. diameter and about 3mm. thickness. In case a Pt-Rh alloy sheet is used as the material, the heat-treatment is carried out at about 1,200 deg.C or below. |
