| About this Abstract |
| Meeting |
Materials Science & Technology 2012
|
| Symposium
|
Raymond W. Buckman, Jr. Memorial Symposium for Refractory Metals and Alloys
|
| Presentation Title |
Post-Irradiation Fracture Toughness of Unalloyed Molybdenum, ODS Molybdenum, and TZM Molybdenum Following Irradiation at 244°C to 507°C |
| Author(s) |
Brian Vern Cockeram, L. L. Snead, Thak Sang Byun, J. L. Hollenbeck |
| On-Site Speaker (Planned) |
Brian Vern Cockeram |
| Abstract Scope |
Commercially available unalloyed molybdenum (Low Carbon Arc Cast (LCAC)), Oxide Dispersion Strengthened (ODS) molybdenum, and TZM molybdenum were neutron irradiated at temperatures of nominally 244°C, 407°C, and 507°C to neutron fluences between 1.0 to 4.6 X 1025 n/m2 (E>0.1 MeV). Post-irradiation fracture toughness testing was performed. All alloys exhibited a Ductile to Brittle Transition Temperature (DBTT) that was defined to occur at 30 ± 4 MPa-m1/2. The highest post-irradiated fracture toughness values (26-107 MPa-m1/2) and lowest DBTT (100-150°C) was observed for ODS molybdenum in the L-T orientation. The finer grain size for ODS molybdenum results in fine laminates that improve the ductile laminate toughening. The results for ODS molybdenum are anisotropic with lower post-irradiated toughness values (20-30 MPa-m1/2) and DBTT (450-600°C) in the T-L orientation. The results for T-L ODS molybdenum are consistent with those for LCAC molybdenum (21-71 MPa-m1/2 and 450-800°C DBTT). The fracture toughness values measured for LCAC and T-L ODS molybdenum at temperatures below the DBTT were determined to be 8-18 MPa-m1/2. Lower fracture toughness values were measured for TZM molybdenum that are attributed to the large carbide precipitates serving as preferential fracture initiation sites. The role of microstructure and grain size on post-irradiated fracture toughness was evaluated by comparing the results for LCAC molybdenum and ODS molybdenum. |
| Proceedings Inclusion? |
Definite: A CD-only volume |