Effect of boron and hydrogen on the electronic structure of Ni{sub 3}Al

Conference · Fri Nov 19 04:00:00 EST 1993

OSTI ID:10136737

Kioussi, N; Watanabe, H; Hemker, R G ^[1]; Johnson, P E ^[2]

---

1. California State Univ., Northridge, CA (United States). Dept. of Physics
2. Lawrence Livermore National Lab., CA (United States)

Using first-principles electronic structure calculations based on the Linear-Muffin-Tin Orbital (LMTO) method, we have investigated the effects of interstitial born and hydrogen on the electronic structure of the Ll{sub 2} ordered intermetallic Ni{sub 3}Al. When it occupies an octahedral interstitial site entirely coordinated by six Ni atoms, we find that boron enhances the charge distribution found in the strongly-bound ``pure`` Ni{sub 3}Al crystal: Charge is depleted at Ni and Al region. Substitution Al atoms for two of the Ni atoms coordinating the boron, however, reduces the interstitial charge density between atomic planes. In contrast to boron, hydrogen appears to deplete the interstitial charge, even when fully coordinated by Ni atoms. We suggest that these results are broadly consistent with the notion of boron as a cohesion enhancer and hydrogen as an embrittler.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 10136737
• Report Number(s): UCRL-JC--115772; CONF-931108--96; ON: DE94009092
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104
ALUMINIUM ALLOYS
BORON
CHARGE DENSITY
ELECTRONIC STRUCTURE
HYDROGEN
INTERMETALLIC COMPOUNDS
METALLURGICAL EFFECTS
NICKEL BASE ALLOYS
PHYSICAL PROPERTIES