Metallurgically improved tip-off tube for a vacuum enclosure
US4919291A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 23, 1987 |
| Grant date | Apr 24, 1990 |
| Priority date | — |
| Expiry date | Nov 23, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J9/40
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A hollow, elongated tip-off tube 12 is comprised of a copper substrate having a layer of gold plating diffused into the surface thereof. The gold is applied over a nickel strike and the tube is heated within a vacuum furnace to diffuse the gold into the copper surface. The gold diffused inner surface of the tube is found to have superior self-welding characteristics and increased strength and durability. The nobility of the inner surface resists the formation of an oxide coating thereon which eliminates the need to clean the inner surface of the tube before pinch-off. Thus, the entrapment of residual cleaning chemicals within the pinch-off area is avoided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.