Influence de nanoparticules sur l'usinabilité et les propriétés mécaniques des matériaux composites

Abstract

Fiber reinforced plastics (FRP) are currently experiencing an increasingly important development in industries. The popularity of these materials come from their high specific mechanical properties, which allow the fabrication of structures much lighter than with traditional materials such as metals. Although wide range of “near net shape” manufacturing processes exist for these materials, machining operations are still needed to obtain the final parts. However, unprecedented difficulties are encountered during FRP machining. This thesis gathers two studies which aim to evaluate the possibility of improving machinability by adding fillers into the matrix. In the first study, carbon fiber reinforced polymers (CFRP) were made by incorporating three fillers into the matrix: wax, nanoclay and a wetting agent. A total of 18 different laminates were machined using a polycrystalline diamond (PCD). In order to characterize the machinability, cutting forces were measured through a dynamometer table and cutting temperatures by thermocouple bonded on the tool. Tensile, flexural and interlaminar shear tests were also performed to inspect the evolution of mechanical properties. Improvement on machinability without deteriorating the mechanical properties were observed, especially with a concentration of 1wt% wax and 2wt% clay where they were the most significant. The second study considers the influence of graphene on glass fiber reinforced polymers (GFRP). Machining tests similar to first study were carried out with a diamond coated tool by chemical vapor deposition (CVD). Roughness was measured on the machined surfaces and interlaminar shear tests executed. Cutting temperatures and forces as well as the roughness were greatly decreased by the addition of graphene, without corrupting the fiber/matrix interaction. This study allowed to demonstrate that addition of additives in FRP is a possibility to be considered in order to improve its machinability. This conclusion turns out to be interesting for the manufacturers, given that addition of additives can reduces the manufacturing costs by reducing the damages occurrence and by maximizing the tool lives.

Date	23 Aug 2019
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Jean-François Chatelain (Supervisor) & Claudiane Ouellet-Plamondon (Co-supervisor)