| 摘要 |
<p>A blank sheet (1) is prepared in corrosion-resistant metal, especially chrome-nickel steel. Primary openings (4) are formed into the sheet by mechanical perforation. It is then thermally-treated. The sheet is rolled to cause size-reduction of the primary openings, which forms filter pores or residual openings having an opening width (f) below 1 micron in size. Sheet thickness (D) is 0.10 mm to 0.90 mm, preferably about 0.5 mm. The primary openings are introduced using a pin (3) roller (2). Primary opening width is between 0.010 and 0.090 mm. Soft-annealing takes place at above 1000[deg]C, preferably at about 1050[deg]C under a protective atmosphere, comprising especially helium or nitrogen. The rolled, perforated sheet is subjected to a chemical trimming process to widen the residual openings of the filter pores. The chemical trimming process is electrolytic de-burring. It is a pickling process. An independent claim is included for the corresponding sub-micron surface filter.</p> |
