Abstract
Rapid development of high technologies has meant that more and more materials need to work under low temperature conditions. In the design of such systems involving thin surface layers, knowledge of the nano-/micromechanical and tribological properties is essential. Therefore, this research is directed at designing and manufacturing a novel cryo-nanomechanical instrument to probe the cryogenic nanomechanical and tribological properties of surfaces. To realise a new dimension to the NanoTest 600 platform, a sub-ambient temperature nanoindentation capability option has been designed specifically to produce accurate basic material properties such as hardness H and Young's modulus E and H/E for the design and property prediction of advanced surface engineered systems. A specially designed purging system has been employed to combat the condensation of water vapour and formation of ice on the samples surfaces at low temperatures, and a localised indenter/sample cooling system was designed with ultra low vibration to aid in the creation of this advanced testing technique. The system has been validated by testing on fused silica carried out at a full range of sub-ambient temperatures. Results presented have shown that the tests performed match the National Institute for Standards and Technology experimental data. Optimum parameters are presented for purging times and gas flow parameters which give accurate reproducibility on the standard sample. The capability of this novel cryo-nanomechanical instrument is demonstrated by way of examples including creep behaviour of bulk polypropylene at sub-ambient temperatures and low temperature mechanical (H and E) and tribological (abrasive wear) properties of diamond-like carbon coatings. This new equipment can provide important materials data for such high technologies as space technology, cryogenic machining, superconductivity and now the booming hydrogen technology.
Original language | English |
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Pages (from-to) | 21-25 |
Number of pages | 5 |
Journal | International Heat Treatment and Surface Engineering |
Volume | 5 |
Issue number | 1 |
Publication status | Published - Mar 2011 |
Keywords
- Cryogenic nanoindentation
- Mechanical properties
- Surface
- Tribological properties
ASJC Scopus subject areas
- Materials Science(all)