Structure and mechanical properties of epitaxial TiN/V[sub 0. 3]Nb[sub 0. 7]N(100) superlattices

Journal Article · Wed Jun 01 04:00:00 EDT 1994 · Journal of Materials Research; (United States)

DOI:https://doi.org/10.1557/JMR.1994.1456· OSTI ID:7046449

Mirkarimi, P B; Barnett, S A ^[1]; Hubbard, K M; Jervis, T R ^[2]; Hultman, L ^[3]

---

1. Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States)
2. Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
3. Department of Physics, Linkoeping University, S-581 83 Linkoeping (Sweden)

Epitaxial TiN/V[sub 0.3]Nb[sub 0.7]N superlattices with a 1.7% lattice mismatch between the layers were grown by reactive magnetron sputtering on MgO(001) substrates. Superlattice structure, crystalline perfection, composition modulation amplitudes, and coherency strains were studied using transmission electron microscopy and x-ray diffraction. Hardness [ital H] and elastic modulus were measured by nanoindentation. [ital H] increased rapidly with increasing [Lambda], peaking at [ital H] values [approx]75% greater than rule-of-mixtures values at [Lambda][approx]6 nm, before decreasing slightly with further increases in [Lambda]. A comparison with previously studied lattice-matched TiN/V[sub 0.6]Nb[sub 0.4]N superlattices, which had nearly identical composition modulation amplitudes, showed a similar [ital H] variation, but a smaller [ital H] enhancement of [approx]50%. The results suggest that coherency strains, which were larger for the mismatched TiN/V[sub 0.3]Nb[sub 0.7]N superlattices, were responsible for the larger hardness enhancement. The results are discussed in terms of coherency strain theories developed for spinodally decomposed materials. Nanoindenter elastic modulus results showed no significant anomalies.

• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 7046449
• Journal Information: Journal of Materials Research; (United States), Journal Name: Journal of Materials Research; (United States) Vol. 9:6; ISSN JMREEE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360203 -- Ceramics
Cermets
& Refractories-- Mechanical Properties
COHERENT SCATTERING
DIFFRACTION
ELECTRON MICROSCOPY
EPITAXY
FILMS
HARDNESS
MECHANICAL PROPERTIES
MICROSCOPY
MICROSTRUCTURE
NIOBIUM COMPOUNDS
NIOBIUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
REFRACTORY METAL COMPOUNDS
SCATTERING
SPUTTERING
SUPERLATTICES
THIN FILMS
TITANIUM COMPOUNDS
TITANIUM NITRIDES
TRANSITION ELEMENT COMPOUNDS
TRANSMISSION ELECTRON MICROSCOPY
VANADIUM COMPOUNDS
VANADIUM NITRIDES
X-RAY DIFFRACTION