| 摘要 |
1,202,28. Improvements relating to lead. ST. JOSEPH LEAD CO. May 2, 1968, [May 3, 1968], No.22534/69. Headings C7D. and C7U. Adsorption of carbon dioxide by partially oxidized lead powder intended for use in the manufacture of dispersion - strengthened lead is prevented by storing the powder, immediately after oxidation, and until required for use, in air while maintaining the powder at a temperature above 50‹ C but below the melting-point of lead. The preferred storage temperatures are in the range 50-100‹ C, where CO2 absorption is minimal. The lead powder may contain 1% by weight of lead oxide calculated as PbO and have an average particle size less than 150 microns, and may be compacted and rolled or extruded to form dispersion strengthened lead after storage as described above, the product being free of undesirable porosity.
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