5553.2:
Low impurity deposition surfaces for liquid flow applications
Abstract
In liquid flow measurement systems organic and inorganic materials are in intimate contact with liquids such as water containing impurities and/or different concentrations of ions such as Na+Cl-, Ca2+CO32-, Fen+. This often leads to abrasion or deposition of impurities which may negatively influence the sensor signal. To obtain a reproducible and time stable sensor signal, a clean, unaltered, and deposition free surface is of crucial importance.
It is well known, that surface properties can be changed by applying thin layers of specific materials or structures. For example self cleaning surfaces have been obtained by specifically structuring the surface (so called ”lotus-effect”), or low-wear, high hardness, and low friction surfaces have been obtained by deposition of nano-crystalline diamond like coatings (DLC).
The aim of the project is to modify surface properties of materials such as stainless steel, glass, silicon, Polyetheretherketon (PEEK), and Teflon in terms of low impurity deposition, low friction and wear, and high mechanical strength. This will be done by applying sub-micrometer thin coatings with structures on the nano-scale level (e.g. non-wetting coatings) and/or by depositing films having nano-scaled grain sizes and thereby exhibiting outstanding mechanical properties (e.g. DLC). These coatings will then be tested in a real mass flow measurement system and evaluated in terms of sensor response, signal stability, and durability.