Improving the ductility of intermetallic compounds by particle-induced slip homogenization

Journal Article · Fri Jul 23 04:00:00 EDT 1999 · Scripta Materialia

DOI:https://doi.org/10.1016/S1359-6462(99)00100-1· OSTI ID:691347

Baker, I ^[1]

---

1. Dartmouth Coll., Hanover, NH (United States). Thayer School of Engineering

Many high-symmetry intermetallic compounds which possess the five independent slip systems required for general plastic flow, e.g. L1{sub 0}-structured, L1{sub 2}-structured and B2-structured compounds, show low ductility at ambient temperature, even when tested in vacuum as high-purity, slow-cooled, carefully machined, electropolished specimens. Intense planar slip can lead to crack nucleation from dislocations pile-ups at low overall strains, even though locally substantial plasticity occurs, producing either intergranular fracture, transgranular cleavage on the slip plane or transgranular cleavage on some other plane. Hydrogen may also increase the slip planarity. Intense planar slip occurs in intermetallics when dislocations are restricted to their original slip plane because of: dissociated dislocation cores; the need to recombine dislocation partials prior to cross-slip: or slip-plane disordering. (Since slip-plane disordering reduces the anti-phase boundary (APB) energy on the slip plane, cross-slip would require that the dislocations move onto a plane with a higher APB energy.)

• Sponsoring Organization: USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States)
• DOE Contract Number: FG02-87ER45311
• OSTI ID: 691347
• Journal Information: Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 4 Vol. 41; ISSN 1359-6462; ISSN SCMAF7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRACKS
DISLOCATIONS
DUCTILITY
INTERMETALLIC COMPOUNDS
MICROSTRUCTURE
NUCLEATION
PARTICULATES
SLIP
VOIDS