Construcción de un prototipo de cubreneumático mediante moldeo por transferencia de resina de compuestos

Abstract

The Light Resin Transfer Molding (LRTM) is a process that can be used to manufacture a variety of parts, such as those used in the automotive industry. This process can use different types of resin, reinforced with natural and synthetic fibers. In this work, a LRTM equipment was assembled and used to obtain composites reinforced glass fiber mats (GF) and 5 cm long randomly distributed abaca fibers (AF). Tire cover prototypes were also manufactured. The unsaturated polyester resin used in this work was formulated incorporating 10 vol% styrene, 90 vol% polyester resin; 0,25 vol% of accelerator and 0,25 vol% catalyst were added to this resin. Reinforced laminates were obtained using this resin and 14 and 20 vol% GF, 12 vol% FA and a 16 vol% hybrid fiber reinforcement (8,6 vol% AF and 7,4 vol% GF). These composites were used to extract samples for tensile, bending and impact testing according to ASTM D3039, D7264 and D5628 standards, respectively. Drilling, cutting, screwing and the surface finish were also evaluated. The quality of the surface finish of the GF and hybrid composites decreased while increasing the fiber volume fraction. The 14 vol% GF reinforced material showed the best property combination: 9776 MPa for Young´s modulus and 60,2 MPa for the tensile strength, 4396 MPa for elastic modulus and 159,3 MPa for bending strength, and a 0,436 J absorbed impact energy. The tire cover prototype was obtained using this material, since the tensile and flexural properties were higher to those of the original tire cover made of polypropylene (PP); however, its absorbed energy was lower. The weight of the tire cover prototype was similar to the original (2.4 kg), even though the density of the composite material (CM) was higher than that of the original (1,31 g/cm3 CM; 0,95 g/cm3 PP). The possibility of conducting studies on the maximum amount of reinforcement to be used in the composite produced by LRTM, without affecting the surface finish, remains open.