Investigation of the machining behavior of unidirectional Alfa (Stipa tenacissima L.)/epoxy composite material.

Nowadays, with regard to many environmental problems, the development of environmentally friendly materials such as natural fiber composites is a real alternative to synthetic fibers. They have many interesting advantages such as their availability, their low cost, their low density, their biodegradable character, their specific resistance properties and their low impact on the environment. The present paper is aimed at fabricating and machining of an epoxy composite material reinforced with Alfa (Stipa tenacissima L.) fibers. The full factorial analysis was used to assess the effect of cutting parameters such as cutting velocity and feed rate on the arithmetic roughness Ra of machined surfaces obtained by down milling and up milling operations. For this purpose, a two flutes high-speed steel (HSS) cutting tool was used. The results showed that the up milling mode provides better surface roughness than down milling mode for almost all machined specimens. The feed rate is the main factor affecting the surface roughness, with a contribution of about 90%. The worst values of arithmetic roughness were observed, at low feed rate (0.05 mm/rev) regardless of the cutting velocity. The results also showed that machining parallel to fibers direction (0°) offers better surface roughness than machining perpendicular to fibers direction (90°). Microscopic and SEM images show some defects such as matrix cracking, cavity, fibers breakage, loss of matrix, fluffing, and thermal damage. [ABSTRACT FROM AUTHOR]