Chemistry: electrical and wave energy – Processes and products – Electrostatic field or electrical discharge
Patent
1993-08-16
1994-10-11
Valentine, Donald R.
Chemistry: electrical and wave energy
Processes and products
Electrostatic field or electrical discharge
20412943, C25F 316
Patent
active
053544374
ABSTRACT:
A method is provided for microelectropolishing a transmission electron microscopy nonhomogeneous multi-element compound foil. The foil is electrolyzed at different polishing rates for different elements by rapidly cycling between different current densities. During a first portion of each cycle at a first voltage a first element electrolyzes at a higher current density than a second element such that the material of the first element leaves the anode foil at a faster rate than the second element and creates a solid surface film, and such that the solid surface film is removed at a faster rate than the first element leaves the anode foil. During a second portion of each cycle at a second voltage the second element electrolyzes at a higher current density than the first element, and the material of the second element leaves the anode foil at a faster rate than the first element and creates a solid surface film, and the solid surface film is removed at a slower rate than the second element leaves the foil. The solid surface film is built up during the second portion of the cycle, and removed during the first portion of the cycle.
REFERENCES:
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Valentine Donald R.
Wisconsin Alumni Research Foundation
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