Conference Paper

Deposition of aluminum coatings on bio-composite laminates

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Abstract

As a result of the increasing environmental awareness, the concern for environmental sustainability and the growing global waste problem, the interest of bio-composites materials is growing rapidly in the last years in order to use them in various engineering fields. Tremendous advantages and opportunities are associated with the use of these materials. On the other hand, some issues are related to the superficial properties of the bio-laminates, in particular the wear properties, the flame resistance and the aesthetic appearance have to be improved in order to extend the application fields of these materials. Aiming to these goals this paper deals with the study of the deposition of aluminum coating through cold spray process on hemp/PLA bio-composites manufactured by using the compression molding technique. Therefore, SEM observations, roughness analyses, bending tests, pin on disk and scratch tests were carried out in order to study the feasibility of the process and to investigate on the properties of the coated samples. The experimental results proved that when the process parameters of the deposition process are properly set, no damages are induced in the composite panel and that the aluminum coating, under specific load conditions, resulted to be able to protect the substrate.

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... To date, several research papers were carried out on CS process for metal/metal depositions [12][13][14][15][16], several theories were proposed in the literature explaining the intriguing bonding mechanisms taking place between the particle and the substrate [17,18]. Low attention was devoted to CS deposition of metal particles on polymer-based substrates and a lot of experimental tests will have to be done, as it remains still an open research topic [19,20]. For instance, Ganesan et al. [21] studied the influence of the substrate polymer's typology on the bonding mechanisms finding that the particles can adhere on the thermoplastic surface thanks to ductile behaviour of the polymer; on the contrary, the particles merely attach on fragile thermosets resins that are subject to breakages during impact. ...
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