Phase analysis and microstructural characterization of SmTiFe sub 11 minus x Co sub x (x = 0,8,11) and DyTiCo sub 11 by transmission electron microscopy

Technical Report · Mon Jan 01 00:00:00 EST 1990

OSTI ID:5744903

Cheng, S F; Demczyk, B G; Laughlin, D E; Wallace, W E

We have examined alloys of composition SmTiFe{sub 11 {minus} x}Co{sub x} (x=0,8,11) and DyTiCo{sub 11} via transmission electron microscopy. Results indicate the sample without Co to be composed primarily of the body-centered tetragonal 1-12 phase with a small amount of alpha-Fe and Fe{sub 2}Ti present. With increasing Co content, the frequency of occurrence of the 2-17 phase increases. In Sm-containing samples, this phase is rhombohedral, while for Dy samples, the hexagonal phase was also found. Correspondingly, we observed an increase in the amount of transition metal-Ti solid solution as the Co concentration increases. In addition, there are orientation relationships between the 1-12 and both 2-17 phases. This is consistent with a coordinate transformation matrix based on the 1-5 structure. Both the 1-12 and 2-17 phases were found to contain antiphase boundaries in annealed samples containing Sm. The 1-12 phase alone contained antiphase boundaries in the DyTiCo{sub 11} sample. These and other results are discussed.

• Research Organization: Carnegie-Mellon Univ., Pittsburgh, PA (USA). Dept. of Metallurgical Engineering and Materials Science
• OSTI ID: 5744903
• Report Number(s): AD-A-232508/2/XAB; CNN: DAAL03-87-K-0150
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COBALT ALLOYS
PHASE STUDIES
DYSPROSIUM ALLOYS
IRON ALLOYS
SAMARIUM ALLOYS
TITANIUM ALLOYS
ANNEALING
CHEMICAL REACTIONS
COORDINATES
CRYSTALLOGRAPHY
ELECTRON MICROSCOPY
MAGNETIC PROPERTIES
MATRICES
MICROSTRUCTURE
ORIENTATION
PHASE TRANSFORMATIONS
SAMPLING
ALLOYS
CRYSTAL STRUCTURE
HEAT TREATMENTS
MICROSCOPY
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
360102* - Metals & Alloys- Structure & Phase Studies