| 摘要 |
<p>The invention relates to an engraved shaft which is entirely or principally made of an aluminum alloy. A raster surface is created on the cylindrical surface of said shaft. Said raster surface comprises recessed cells having a predetermined volume. A layer of oxide-ceramics is formed on the raster surface by process of electrolytic oxidation, whereby such a layer, which has a depth between 15 and 50 micrometers and a micro-hardness between 700 and 1500 Hv, adequately reproduces the outline of the external surface of the raster. The high hardness and strength of the oxide-ceramic layer enable the raster cells to maintain a correct shape and dimensions for a long time during the use of the shaft. Said oxide-ceramic layer may be additionally impregnated with metal or organic materials so as to further strengthen the raster surface, increase the corrosion resistance thereof and provide it with special properties (oleophilic, absorbent, hydrophobic, etc.) as required in various systems involving the dosed transfer of liquids and suspensions.</p> |
