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Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
Osmium diboride, an ultra-incompressible, hard material
Robert W Cumberland1, Michelle B Weinberger, John J Gilman
1Department of Chemistry and Biochemistry, University of California, Los Angeles, 90095-1569, USA.
Journal of the American Chemical Society
|May 19, 2005
Summary
Researchers identified OsB2 as a superhard material by focusing on high electron density and bond covalency. This material exhibits exceptional hardness and incompressibility, rivaling diamond.
Area of Science:
- Materials Science
- Solid State Physics
- Crystallography
Background:
- The development of wear- and scratch-resistant materials is crucial for advanced technological applications.
- Superhard materials are essential for demanding industrial processes, driving research into novel compounds.
- Identifying materials with superior mechanical properties, such as high hardness and incompressibility, remains a significant scientific challenge.
Purpose of the Study:
- To identify ultra-incompressible and superhard materials using specific design parameters.
- To investigate Osmium Diboride (OsB2) as a potential superhard material candidate.
- To experimentally determine the bulk modulus and hardness of OsB2.
Main Methods:
- Application of design principles focusing on high valence electron density and high bond covalency.
- In situ high-pressure X-ray diffraction to measure the bulk modulus of OsB2.
- Scratch testing against a sapphire window to evaluate the material's hardness.
Main Results:
- Osmium Diboride (OsB2) was identified as a superhard material.
- The measured bulk modulus of OsB2 is 365-395 GPa, indicating high incompressibility.
- OsB2 demonstrated a hardness exceeding 2000 kg/mm², surpassing that of sapphire.
Conclusions:
- Osmium Diboride (OsB2) exhibits properties of an ultra-incompressible and superhard material.
- The material's anisotropic structure contributes to its unique mechanical characteristics.
- OsB2 presents a promising alternative to existing superhard materials for various applications.
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