Radiation-induced segregation and precipitation in molybdenum-rhenium alloys

Conference · Sat Feb 01 00:00:00 EST 1986

OSTI ID:5831801

Erck, R A; Wayman, C M; Rehn, L E

Specimens of Mo-7 at. % Re and Mo-30 at. % Re were irradiated with 1.8 MeV /sup 4/He/sup +/ ions at elevated temperatures. Radiation-induced segregation of Re was measured during irradiation by in situ Rutherford backscattering spectrometry. Segregation of the undersized Re atoms in the same direction as the defect fluxes, i.e., toward the external surface, was observed. The amount of Re enrichment in the near-surface region was measured as a function of temperature and of dose at a calculated near-surface displacement rate near 1 x 10/sup -4/dpa/s. Segregation was observed at temperatures from 800 to 1500/sup 0/C in Mo-7Re, and from 850 to 1225/sup 0/C in Mo-30Re. Irradiated disks were examined by transmission electron microscopy. Precipitates of Chi phase were observed on grain boundaries, or in a thin layer at the irradiated surface in Mo-30Re after irradiation at temperatures from 750 to 1075/sup 0/C. Frequently, Chi precipitates formed with a crystallographic twin orientation with respect to the host matrix. No voids were observed for doses up to 1.6 dpa.

• Research Organization: Argonne National Lab., IL (USA); Illinois Univ., Urbana (USA). Dept. of Metallurgy and Mining Engineering
• DOE Contract Number: W-31-109-ENG-38
• OSTI ID: 5831801
• Report Number(s): CONF-860605-6; ON: DE86007521
• Resource Relation: Conference: 13. international symposium on the effects of radiation on materials, Seattle, WA, USA, 23 Jun 1986; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
MOLYBDENUM ALLOYS
PHYSICAL RADIATION EFFECTS
RHENIUM ALLOYS
HELIUM IONS
MEV RANGE 01-10
MICROSTRUCTURE
SEGREGATION
TRANSMISSION ELECTRON MICROSCOPY
ALLOYS
CHARGED PARTICLES
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
ENERGY RANGE
IONS
MEV RANGE
MICROSCOPY
RADIATION EFFECTS
360106* - Metals & Alloys- Radiation Effects