Manufacture of complex shaped Cr.sub.3 C.sub.2 /Al.sub.2 O.sub.3 components by injection molding technique
US5993726A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1997 |
| Grant date | Nov 30, 1999 |
| Priority date | — |
| Expiry date | Apr 22, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB28B11/243
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The purpose of this invention is to manufacture complex shaped Cr.sub.3 C.sub.2 /Al.sub.2 O.sub.3 components efficiently with effective cost. Chromium carbide, which is quite chemically inert at elevated temperature, is added into an alumina matrix for toughening purposes. Chromium carbide and alumina ceramic powders are mixed with binders to form a solidified suspension. The suspension is then crushed, heated, and injected into green products. Controlled solvent and thermal debinding processes are followed before performing pressureless sintering. Samples are sintered in pre-treated argon gas with minimum oxygen partial pressure, or in vacuum for controlling the phase stability and microstructure for tailoring mechanical properties. The processing parameters for injection molding, the composition design of binders and ceramic composites, and the techniques for controlling the phase transformation of chromium carbide are developed. A near-net shape complex component with minimum after machining can be manufactured. The injection molding and pressureless sintering process make the mass production possible. Optimized properties of 97.8% in the theoretical density, 500 Mpa in strength…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.