配方类型: |
METALS |
配方说明: |
To Mark Metal Articles by Electrolytic Etching (British Patent 551,771) |
配方组成: |
On an electrical conducting block, conveniently made of graphite, with the top surface machined or ground flat, a sheet of blotting paper is placed, which is wetted with an electrical conducting solution, such as Nitric Acid/5 Water/88 Hydrochloric Acid (Conc)/7 |
配制方法: |
An electrically insulating stencil, such as a waxed stencil paper, on which the required marking or wording has been typed or printed is placed on the absorbent, face down. The flat face of the metallic article to be marked, e.g., of high-speed steel or of "Stellite" is placed on the stencil and electrical contact is made by placing a weighted electrically conducting block (conveniently made of graphite) on top of the article to ensure good contact between the stencil and the article. The graphite blocks are then connected to a source of electrical direct current supply, the block on top being the anode. Any force of direct current from 3 to 220 volts cann be used, but 12 volts is used without danger to the operator. The time required for the etching varies according to the voltage, the current, and the number of words to be etched. If a force of 12 volts is used, connected through the apparatus, 5 seconds are required to etch six syllables on "Stellite." With a voltage of 220, connected through the |
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