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Aerospace structural materials handbook supplement grcop-84
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Ellis, David L. |
| Copyright Year | 2001 |
| Description | GRCop-84 is a high strength-high conductivity copper-based alloy developed at NASA Glenn Research Center for combustion chamber liners of regeneratively cooled rocket engines. It also has promise for other high heat flux applications operating at temperatures up to 700 C (1292 F) and potentially higher. The alloy must be made by powder metallurgy techniques such as gas atomization. Slower cooling rates such as those experienced during casting do not develop a proper microstructure. Once made into powder, the alloy exhibits excellent processability using conventional consolidation and forming techniques, e.g., extrusion and rolling. GRCop-84 is strengthened by a combination of dispersion and precipitation strengthening by fine (50-500 nanometer (2-20 microinch)) Cr2Nb particles and Hall-Petch strengthening from a fine copper grain size. The presence of a high volume fraction of particles prevents grain boundary sliding at high temperatures and contributes to the alloy's overall good high temperature mechanical properties. Maximum thermal conductivity is obtained by using two alloying elements (Cr, Nb) with limited solubility in solid Cu that form a high temperature intermetallic compound with an even lower solid solubility. The resulting matrix of the alloy is nearly pure copper. The limited solubility also minimizes Cr2Nb particle coarsening at elevated temperatures and enhances microstructural and mechanical property stability. Further enhancement of the microstructural stability is obtained by using a high volume fraction (approx. 14 vol.%) of Cr2Nb particles that effectively pin grain growth. |
| File Size | 1054598 |
| Page Count | 57 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20020070630 |
| Archival Resource Key | ark:/13960/t50g8mh44 |
| Language | English |
| Publisher Date | 2001-10-24 |
| Access Restriction | Open |
| Subject Keyword | Metals And Metallic Materials Dispersion Strengthening Copper Alloys Aircraft Construction Materials Intermetallics Mechanical Properties Thermal Conductivity High Temperature Powder Metallurgy Microstructure High Strength Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
