Electrolytic polishing of niobium parts
Abstract
Abstract A METHOD OF ELECTROLYTICALLY POLISHING PARTS MADE OF NIOBIUM, WHICH COMPRISES IMMERSING THE NIOBIUM PARTS AS AN ANODE IN AN ELECTROLYTE SUBSTANTIALLY COMPOSED BY WEIGHT OF 86 TO 93% H2SO4, 1.5 TO 4.0% HF AND 5.5 TO 10.0% H2O, MAINTAINING THE ELECTROLYTE DURING THE POLISHING ACTION AT A SUBSTANTIALLY CONSTANT TEMPERATURE BETWEEN ABOUT 15* AND 50*C., APPLYING BETWEEN THE NIOBIUM PART AND AN IMMERSED CATHODE A SUBSTANTIALLY CONSTANT UNI- DIRECTIONAL VOLTAGE OF ABOUT 9 TO 15 VOLTS WHEREBY ELECTROLYTE CURRENT OSCILLATIONS OCCUR WHOSE AMPLITUDE DECAYS DUE TO PROGESSSING OXIDATION OF THE NIOBIUM SURFACE. UPON SUFFICIENT DECAY OF THE OSCILLATIONS, THE VOLTAGE IS DISCONNECTED UNTIL THE OXIDE IS SUBSTANTIALLY DISSOLVED. PREFERABLY THE SAME CYCLE IS MANY TIMES REPEATED.
Inventors
- 👤 Heinrich Diepers
- 👤 Otto Schmidt
Bibliographic Details
Claims Analysis
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| 3.5 Years (Year 4) | 1975-09-05 | 1976-03-06 | 1976-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-05 | 1980-03-06 | 1980-09-05 | $3760.00 | Window Closed / Lapsed |
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