High-Temperature Nanoindentation of an Advanced Nano-Crystalline W/Cu Composite

Nanomaterials

Michael Wurmshuber¹  Mingyue Zhao¹  Michael Burtscher¹  Daniel Kiener¹  Alexander Leitner²  Johann Kappacher²  Verena Maier-Kiener²  Manuel Pfeifenberger³ 

[1] Department of Materials Science, Chair of Materials Physics, University of Leoben, Jahnstraße 12, 8700 Leoben, Austria;Department of Materials Science, Chair of Physical Metallurgy and Metallic Materials, University of Leoben, Roseggerstraße 12, 8700 Leoben, Austria;Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, University of Leoben, Jahnstaße 12, 8700 Leoben, Austria;

关键词: W/Cu composite;    nanocrystalline;    high-pressure torsion;    microstructure;    nanoindentation;   

DOI  :  10.3390/nano11112951

来源: DOAJ

【 摘 要 】

The applicability of nano-crystalline W/Cu composites is governed by their mechanical properties and microstructural stability at high temperatures. Therefore, mechanical and structural investigations of a high-pressure torsion deformed W/Cu nanocomposite were performed up to a temperature of 600 °C. Furthermore, the material was annealed at several temperatures for 1 h within a high-vacuum furnace to determine microstructural changes and surface effects. No significant increase of grain size, but distinct evaporation of the Cu phase accompanied by Cu pool and faceted Cu particle formation could be identified on the specimen′s surface. Additionally, high-temperature nanoindentation and strain rate jump tests were performed to investigate the materials mechanical response at elevated temperatures. Hardness and Young′s modulus decrease were noteworthy due to temperature-induced effects and slight grain growth. The strain rate sensitivity in dependent of the temperature remained constant for the investigated W/Cu composite material. Also, the activation volume of the nano-crystalline composite increased with temperature and behaved similar to coarse-grained W. The current study extends the understanding of the high-temperature behavior of nano-crystalline W/Cu composites within vacuum environments such as future fusion reactors.

【 授权许可】

Unknown