Electric arc vacuum melting processes
Abstract
Abstract A process for heating or treating metals without substantially contaminating the metal to be heated or treated comprises introducing the metal into an at least partially evacuated chamber and producing an electric arc therein from the arcing surface-forming tip of a nonconsumable electrode to a surface of opposite polarity while fluid cooling the tip to conduct heat flux therefrom and generating a magnetic field adjacent the tip which causes the arc therefrom to move substantially continuously over the arcing surface, thereby preventing the arc spot from dwelling at any point on the arcing surface a sufficient time to raise the temperature at said point to a value at which substantial sublimation or evaporation of material from the arcing surface takes place.
Inventors
- 👤 Armin M Bruning
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |