Considering the perspective of environmental and energy problems, to decrease friction and wear of sliding surfaces, vigorous attempts were taken into research and development projects for tribological coating films. In specific, diamond-like carbon (DLC) coatings have superior low-friction and anti-wear characteristics compared to other coatings, and tribology scientists and technicians are attracting a good deal of attention towards these coatings. However, the friction and wear characteristics of DLC coatings rely on their applications as well as their manufacturing procedures and it is therefore essential to select suitable DLC coatings according to their requirement of use and engineering reasons. Using a combination of methane and tetrafluoromethane gasses, fluorinated amorphous carbon films were placed on soft alloy substrates using a radio frequency plasma improved chemical vapor deposition method. In order to improve adhesion between F-DLC and alloy, a Si interlayer was pre-coated by physical vapor deposition process. Using X-ray diffraction spectroscopy, Raman spectroscopy, Fourier transforming infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy, the structure and surface characteristics of F-DLC coatings were explored. The mechanical characteristics were Nano-indentation and micro-scratch adhesion assessed the mechanical characteristics. The findings showed that a mild inclusion of fluorine content in DLC coatings could still retain acceptable mechanical characteristics, which, on the other hand, has notable advantages in terms of blood compatibility and anti-corrosion.
Considerando la prospettiva dei problemi ambientali ed energetici, per ridurre l'attrito e l'usura delle superfici scorrevoli, sono stati intrapresi energici tentativi di progetti di ricerca e sviluppo per i film di rivestimento tribologico. In specifici rivestimenti di carbonio (DLC) a forma di diamanti hanno caratteristiche di basso attrito e anti-usura superiori rispetto ad altri rivestimenti, e gli scienziati e i tecnici di tribologia stanno attirando molta attenzione su questi rivestimenti. Tuttavia, le caratteristiche di attrito e usura dei rivestimenti DLC dipendono dalle loro applicazioni e dalle loro procedure di fabbricazione ed è pertanto essenziale selezionare rivestimenti DLC adeguati in base alle loro esigenze d'uso e ai motivi tecnici. Utilizzando una combinazione di gas metano e tetrafluorometano, i film di carbonio amorfo fluorurati sono stati collocati su substrati di leghe morbide utilizzando un plasma a radiofrequenza migliorata metodo di deposizione chimica dei vapori. Per migliorare l'aderenza tra F-DLC e lega, un interstrato Si è stato prerivestito dal processo di deposizione del vapore fisico. Sono state esaminate la spettroscopia di diffrazione a raggi X, la spettroscopia Raman, la spettroscopia Fourier che trasforma infrarossi, la spettroscopia fotoelettronica a raggi X e la microscopia elettronica a scansione, la struttura e le caratteristiche superficiali dei rivestimenti F-DLC. Le caratteristiche meccaniche erano il rientro della nano e l'aderenza del micro-graffio valutava le caratteristiche meccaniche. I risultati hanno dimostrato che una lieve inclusione del contenuto di fluoro nei rivestimenti DLC potrebbe ancora mantenere caratteristiche meccaniche accettabili, che, d'altro canto, presentano notevoli vantaggi in termini di compatibilità del sangue e anticorrosione.
Diamond-like carbon coatings on soft alloys with flourinated interlayer
PUVANESWARAN, RAVISANKAR
2018/2019
Abstract
Considering the perspective of environmental and energy problems, to decrease friction and wear of sliding surfaces, vigorous attempts were taken into research and development projects for tribological coating films. In specific, diamond-like carbon (DLC) coatings have superior low-friction and anti-wear characteristics compared to other coatings, and tribology scientists and technicians are attracting a good deal of attention towards these coatings. However, the friction and wear characteristics of DLC coatings rely on their applications as well as their manufacturing procedures and it is therefore essential to select suitable DLC coatings according to their requirement of use and engineering reasons. Using a combination of methane and tetrafluoromethane gasses, fluorinated amorphous carbon films were placed on soft alloy substrates using a radio frequency plasma improved chemical vapor deposition method. In order to improve adhesion between F-DLC and alloy, a Si interlayer was pre-coated by physical vapor deposition process. Using X-ray diffraction spectroscopy, Raman spectroscopy, Fourier transforming infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy, the structure and surface characteristics of F-DLC coatings were explored. The mechanical characteristics were Nano-indentation and micro-scratch adhesion assessed the mechanical characteristics. The findings showed that a mild inclusion of fluorine content in DLC coatings could still retain acceptable mechanical characteristics, which, on the other hand, has notable advantages in terms of blood compatibility and anti-corrosion.File | Dimensione | Formato | |
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https://hdl.handle.net/10589/149452