| 摘要 |
1,183,642. Porous metal products. INTERNATIONAL NICKEL Ltd. Aug. 9, 1968 [Aug.17, 1967; April 19, 1968], Nos. 38036/67 and 18697/68. Heading C7D. A process for the production of a metal replica of a fibrous material comprises so impregnating a natural cellulosic fibrous material with a solution of one or more thermally decomposable metal salts that the solution enters the fibres, drying the impregnated material, and by a single heating in a reducing atmosphere destroying the cellulosic material, decomposing the salt or salts to metal and sintering the resultant metal to produce a coherent metal body having a porosity corresponding to the pores within the fibres as well as to the gaps between them in the starting material. The cellulosic fibrous material may be cotton in sheet form, e.g. woven or knitted cotton or cotton wool, cotton or sisal thread, jute sacking, blotting paper or paper pulp. The metal may be Fe, Co, Ni, Cu, or alloys thereof, or W, Mo, Ag, Au or a platinum group metal, but Ni is preferred and NiCl 2 is the preferred impregnating salt. The heating step is carried out at a temperature of at least 900‹ C. in which case the heating time does not exceed 60 minutes, but heating at more than 1000‹ C. for not more than 30 minutes is preferred, the heating in each case being carried out in a reducing atmosphere such as cracked ammonia. A metal plaque may be formed from porous sheets made by the above process, by bonding said sheets by compacting and/or sintering and the plaque may be impregnated to form an alkaline battery plate, e. g. a bonded stack of Ni plates may be impregnated with NI(OH) 2 by conventional methods. |
