Synthesis by plasma-enhanced chemical-vapor deposition and characterization of siliconlike films with hydrophobic functi
- PDF / 1,159,027 Bytes
- 9 Pages / 585 x 783 pts Page_size
- 104 Downloads / 207 Views
A. Merlo Ce.S.I. Centro Studi Industriali-R&D and Advanced Engineering Department, 20133 Milano, Italy
A. Srikantha Phani Cambridge University, Engineering Department, Cambridge CB2 1TN, United Kingdom
L. Laguardia Istituto di Fisica del Plasma Consiglio Nazionale delle Ricerche (CNR), 20162 Milano, Italy (Received 25 July 2007; accepted 4 January 2008)
Amorphous siliconlike films with hydrophobic functionalities have been deposited by plasma-enhanced chemical-vapor deposition on carbon-fiber-reinforced polymer (CFRP) unidirectional laminates used for micromechanical applications where high strength-to-weight and high stiffness-to-weight ratios are required. To improve long-term geometrical stability in ultrahigh-precision machine structures, hydrophobic CFRP materials are desirable. Three layers have been grown with different plasma-process parameters from a mixture of hexamethyldisiloxane, O2, and Ar. Chemical composition, water contact angle, surface energy, morphology, and tribological properties have been evaluated to choose the one that best fulfills hydrophobicity, wear, and scratch resistance. Wear tests have also been carried out on CFRP laminates coated with a polyurethane layer to compare the wear performance of the above specimens with that of a conventional hydrophobic coating. Scanning electron microscope images show a very good adhesion of the films to the composite substrate because the failure of the film and of the substrate (such as fiber failure) take place simultaneously.
I. INTRODUCTION
In this article, a chemical-physical and tribological characterization of hydrophobic amorphous siliconlike thin films (a-Si:Ox:Cy:Hz) deposited by plasma-enhanced chemical-vapor deposition (PECVD) on carbon-fiberreinforced polymer (CFRP) laminates has been carried out. Fiber-reinforced polymers are composite materials that are made up of two component materials, matrix and reinforcement, with significantly different chemicalphysical properties, which remain separate within a finished structure. In this specific case, the matrix is an epoxy resin, which surrounds and supports the reinforcement of carbon fibers with a 10-m diameter, and the complex structure is a laminate, originating from the sua)
Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/JMR.2008.0123 1042 J. Mater. Res., Vol. 23, No. 4, Apr 2008 http://journals.cambridge.org Downloaded: 18 Mar 2015
perposition of a set of unidirectional plies (Fig. 1). These materials are used for mechanical applications where structural design is driven by high strength-to-weight and high stiffness-to-weight ratio requirements. In particular applications, composite materials with hydrophobic functionalities are desirable. Typical examples are ultrahigh precision machine structures (e.g., micromilling machines, grinding machines, and measuring machines) for which high mechanical performance (i.e., low weight and high stiffness) as well as extremely good long-term geometrical stability are required. In this case, water absorptio
Data Loading...
