<div class="csl-bib-body">
<div class="csl-entry">Hahn, R., Tymoszuk, A. A., Wojcik, T., Ntemou, E., Hunold, O., Polcik, P., Kolozsvári, S., Primetzhofer, D., Mayrhofer, P. H., & Riedl-Tragenreif, H. (2023). Unraveling the superlattice effect for hexagonal transition metal diboride coatings. <i>Scripta Materialia</i>, <i>235</i>, Article 115599. https://doi.org/10.1016/j.scriptamat.2023.115599</div>
</div>
-
dc.identifier.issn
1359-6462
-
dc.identifier.uri
http://hdl.handle.net/20.500.12708/191742
-
dc.description.abstract
Superlattice structures enable the simultaneous enhancement in hardness (H) and fracture toughness (KIC) of ceramic-like coatings. While a deeper understanding of this effect has been gained for fcc-structured transition metal nitrides (TMN), hardly any knowledge is available for hexagonal diborides (TMB₂). Here we show that superlattices can—similarly to nitrides—increase the hardness and toughness of diboride films. For this purpose, we deposited TiB₂/WB₂ and TiB₂/ZrB₂ superlattices with different bilayer periods (Λ) by non-reactive sputtering. Nanoindentation and in-situ microcantilever bending tests yield a distinct H peak for the TiB₂/WB₂ system (45.5 ± 1.3 GPa for Λ = 6 nm) but no increase in KIC related to a difference in shear moduli (112 GPa). Contrary, the TiB₂/ZrB₂ system shows no peak in H, but for KIC with 3.70 ± 0.26 MPa∙m1/2 at Λ = 4 nm originating from differences in lattice spacing (0.14 Å), hence causing coherent stresses retarding crack growth.
en
dc.language.iso
en
-
dc.publisher
PERGAMON-ELSEVIER SCIENCE LTD
-
dc.relation.ispartof
Scripta Materialia
-
dc.rights.uri
http://creativecommons.org/licenses/by/4.0/
-
dc.subject
Diboride coatings
en
dc.subject
Fracture toughness
en
dc.subject
Micromechanical testing
en
dc.subject
Physical vapor deposition
en
dc.subject
Superlattice
en
dc.title
Unraveling the superlattice effect for hexagonal transition metal diboride coatings
