Abstract

Minimizing mechanical losses and friction invehicle engines would have a great impact on reducingfuel consumption and exhaust emissions, to the benefit ofenvironmental protection. With this scope, laser surfacetexturing (LST) with femtosecond pulses is an emergingtechnology, which consists of creating, by laser ablation,an array of high-density microdimples on the surface of amechanical device. The microtexture decreases the effectivecontact area and, in case of lubricated contact, actsas oil reservoir and trap for wear debris, leading to anoverall friction reduction. Depending on the lubricationregime and on the texture geometry, several mechanismsmay concur to modify friction such as the local reductionof the shear stress, the generation of a hydrodynamic liftbetween the surfaces or the formation of eddy-like flowsat the bottom of the dimple cavities. All these effectshave been investigated by fabricating and characterizingseveral LST surfaces by femtosecond laser ablation withdifferent features: partial/full texture, circular/ellipticaldimples, variable diameters, and depths but equivalentareal density. More than 85% of friction reduction hasbeen obtained from the circular dimple geometry, but theelliptical texture allows adjusting the friction coefficientby changing its orientation with respect to the slidingdirection.

Autore Pugliese

• Ancona Antonio

Tutti gli autori

• A. Ancona ; G. Carbone ; M. De Filippis ; A. Volpe; P.M. Lugarà

Titolo volume/Rivista

Advanced optical technologies

Anno di pubblicazione

2014

ISSN

2192-8584

ISBN

Non Disponibile

Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile

Numero di citazioni Scopus

Non Disponibile

Ultimo Aggiornamento Citazioni

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Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile