Influence of solute segregation on the dislocation structure of small and large angle (001) twist boundaries in Fe-Sb alloys

Journal Article · Sun May 01 00:00:00 EDT 1988 · Scr. Metall.; (United States)

DOI:https://doi.org/10.1016/S0036-9748(88)80192-3· OSTI ID:6362939

Lin, C H; Sass, S L

In alloy systems where there is limited solubility in the solid solution solute atoms segregate to grain boundaries giving local compositions at the interface typically at the monolayer level. The practical consequence of such segregation in Fe-base alloys is frequently the embrittlement of the grain boundary region, making it susceptible to fracture at relatively low stresses. It is interesting to note that in polycrystalline Ni/sub 3/Al, which is intrinsically brittle, B segregation to grain boundaries and changes in stoichiometry, make the material ductile. It is of considerable importance to learn how the presence of solute changes the fracture resistance of grain boundaries. Briant and Messmer suggested that segregation causes a change in the nature of the electronic bonding at the interface, which is believed to influence its cohesive strength. Hart suggested that segregation causes a change in the structure of the boundary and in this manner controls its resistance to fracture. At present there is no experimental evidence concerning the bonding at grain boundaries in Fe-Te, and in Cu-Bi. Others have reported a characteristic grain boundary morphology in the presence of solute segregation, in the form of faceting. While both sets of observations lead to the suggestion that faceting results from solute segregation, neither study examined the structure of the same boundary in both the clean and segregated states.

• Research Organization: Dept. of Materials Science and Engineering, Cornell Univ., Ithaca, NY (US)
• OSTI ID: 6362939
• Journal Information: Scr. Metall.; (United States), Journal Name: Scr. Metall.; (United States) Vol. 22:5; ISSN SCRMB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
360103 -- Metals & Alloys-- Mechanical Properties
ALLOYS
ALUMINIUM ALLOYS
ANTIMONY ALLOYS
BOUNDARY CONDITIONS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
CRYSTALS
DISLOCATIONS
DISPERSIONS
EMBRITTLEMENT
FRACTURE PROPERTIES
GRAIN BOUNDARIES
GRAIN ORIENTATION
INTERFACES
IRON ALLOYS
LINE DEFECTS
MECHANICAL PROPERTIES
MICROSTRUCTURE
MIXTURES
NICKEL ALLOYS
ORIENTATION
PNICTIDES
POLYCRYSTALS
SOLID SOLUTIONS
SOLUBILITY
SOLUTES
SOLUTIONS
STRUCTURAL CHEMICAL ANALYSIS