Radiation-induced amorphization of ordered intermetallic compounds CuTi, CuTi sub 2 , and Cu sub 4 Ti sub 3 : A molecular-dynamics study

Journal Article · Fri Mar 01 04:00:00 EST 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.5243· OSTI ID:5492609

Sabochick, M J ^[1]; Lam, N Q ^[2]

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1. Department of Engineering Physics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433 (USA)
2. Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (USA)

Solid-state amorphization resulting from the introduction of chemical disorder and point defects in the ordered intermetallic compounds CuTi, CuTi{sub 2}, and Cu{sub 4}Ti{sub 3} was investigated, with use of the isobaric-isothermal molecular-dynamics method in conjunction with embedded-atom potentials. Antisite defects were produced by randomly exchanging Cu and Ti atoms, and vacancies and interstitials were created by removing atoms at random from their normal sites and inserting atoms at random positions in the lattice, respectively. The potential energy, volume expansion, and pair-correlation function were calculated as functions of the numbers of atom exchanges and point defects. The results indicated that, although both chemical disordering and point-defect introduction increased the system energy and volume, the presence of point defects was essential to trigger the crystalline-to-amorphous transition. By comparing the pair-correlation function calculated after the introduction of point defects with that of the quenched liquid alloy, the critical damage dose (in dpa, displacements per atom) for amorphization was estimated for each compound: {similar to}0.7 dpa for CuTi, {similar to}0.5 dpa for CuTi{sub 2}, and {similar to}0.6 dpa for Cu{sub 4}Ti{sub 3}. At the onset of amorphization, the volume expansions were found to be {similar to}1.9%, {similar to}3.7%, and {similar to}1.7% for these respective compounds. In general, the results obtained in the present work are in good agreement with experimental observations.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5492609
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 43:7; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360106* -- Metals & Alloys-- Radiation Effects
ALLOYS
AMORPHOUS STATE
COLLISIONS
COPPER ALLOYS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELECTRON COLLISIONS
INTERMETALLIC COMPOUNDS
INTERSTITIALS
PHASE TRANSFORMATIONS
PHYSICAL RADIATION EFFECTS
POINT DEFECTS
RADIATION EFFECTS
TITANIUM ALLOYS
VACANCIES