Method for casting core removal
US7882884B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2007 |
| Grant date | Feb 8, 2011 |
| Priority date | — |
| Expiry date | Sep 3, 2029 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22D29/002
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
To destructively remove a casting core from a cast part, the part is exposed to a combination of nitric acid and sulfuric acid. The combination may have, by volume, a nitric acid concentration of 4-20 times the sulfuric acid concentration. The combination may be an aqueous solution including, by volume, 40-60% nitric acid and 3-10% sulfuric acid. The method may remove a ceramic casting core and a refractory metal-based casting core. A first leaching step may remove a major portion of the ceramic casting core and may comprise alkaline leaching. A second leaching step may remove a major portion of the refractory metal-based casting core and may comprise acid leaching. The acid leaching may comprise the combination of nitric acid and sulfuric acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.