State of the art on the generation of aerosols during the mechanical solicitation of the materials
Résumé
The overwhelming use of nanoparticles in contemporary applications have brought huge potential risks to the workers and consumers due to their release during their use. This release is usually in the form of polydispersed aerosols, from nano to micronic size range. Towards the safety concern of this release, in-vivo tests and analyses are being carried out (Kohler 2008, Wohlleben 2011). Various exposure models have also been devised (Duuren-Stuurman 2011, Schneider 2011) but surprisingly very limited studies have been done concentrating on how and why they are being released. The present work deals with such an aspect towards the release of the aerosol particles. This release is a direct result of the wear or fretting of surfaces when solicitated mechanically. This wear solely depends on the parental contact conditions exhibiting various regimes of different stress states. These contact conditions have been studied (Greenwood and Williamson 1966, Kapoor et al. 1994, Jiang et al. 1998, Eriten et al. 2011 etc.) to explain different surface phenomena but no concern was given towards them getting airborne. So, there arises a need to bridge these wear or contact conditions studies with the present ongoing aerosol research. This bridge can prove a crucial step towards the control and minimization of their release. Facilitating this approach, here an attempt has been made to explain these release mechanisms and principles conceived up to date, methods being adopted towards their release, state of the art instrumentation available for their characterization and the process and mathematical modeling techniques available for use.