Electrode component thermal bonding
US6483070B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2001 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Sep 26, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H1/3442
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An electrode for supporting an arc in a plasma arc torch is provided and includes an emissive element for supporting the arc, which may be formed of hafnium; a relatively non-emissive member comprising a first metal including silver, which is positioned to circumscribe a front surface of the emissive element; and a metallic holder for holding the non-emissive member. The holder is in one embodiment made of a copper alloy including a major portion of copper and a minor portion of another metal, such as nickel. After assembly, the electrode is subjected to a heat treatment that causes a thermal bonding between the relatively non-emissive member and the metallic holder, which, during subsequent operation of the electrode, provides good thermal conduction away from the emissive element and improves the consumable life of the electrode. Advantageously, during the heating step, the nickel attenuates the eutectic reaction between the copper and the silver that would otherwise occur and allows bonding over a wide range of temperatures and heating cycle durations. In addition, the temperature at which bonding occurs between the non-emissive member and the holder is also raised. As a result,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.