| 摘要 |
1281113 Very high pressure apparatus KENNAMETAL Inc 9 March 1970 [19 March 1969] 11076/70 Heading B1X [Also in Divisions B3 B5 and C1] An apparatus suitable for e.g. diamond manufacture, comprises a ring 10 of cemented tungsten carbide press fitted into a heavy surrounding steel ring with pressure pistons 12 entering from each end. Fitted into the ring is a cell comprising an inner alumina sleeve 16 surrounded by a graphite tube 18 and further surrounded by an alumina tube 20. The charge 22 being placed within tube 16. The ends of tube 16 are closed by a pair of alumina discs 26 over which is a metal disc 28 extending the whole diameter of tube 20 and in electrical contact with graphite tube 18 resting on disc 28 is a metal ring 29 having an alumina plug 29 within it. Between the cell and ring 10 are sealing sleeves 30 of electrical insulating material having the characteristics of pyrophyllite or talc, and having disposed between them a metal sleeve 32. In operation the cell is inserted in the apparatus and pressure is applied by means of pistons 12 while tube 18 is heated by passing electric current through it via pistons 12 discs 28 and rings 29 enabling conditions of e.g. 50,000-70,000 atmospheres pressure and 1200-2000‹C to be obtained. When the charge 22 is carbon, holes 25 may be drilled into it to receive metal rods or wires 24. In another embodiment (Fig. 11) the cell has an outer alumina tube 200 a graphite sleeve 204 and inner alumina sleeve 206 fitted inside. The inside of the cell is divided into a number of compartments by means of alumina dividing members 210 into which compartments are placed the charges. Although the outer tube of the cell is conveniently of circular external cross-section, its internal crosssection may conveniently be of e.g. square, triangular or elliptical cross-section to enable the manufacture of members comprising diamond disposed in a matrix metal (see Division C1) of convenient shape making cutting tool inserts without first separating the diamond from the matrix metal (see Division B3). |
