CHARPY IMPACT TEST IN POLYESTER MATRIX COMPOSITES REINFORCED WITH SHORT SISAL AND JUTE FIBERS

• DOI: 10.22533/at.ed.3173382321118

• Palavras-chave: Sisal and jute natural fibers, polyester resin, Charpy impact test, composite materials.

• Keywords: Sisal and jute natural fibers, polyester resin, Charpy impact test, composite materials.

• Abstract: Natural lignocellulosic fibers (NLFs) are increasingly being studied and applied as substitutes for fibers of synthetic origin. The advantage is the fact that NLFs are renewable, biodegradable, have good specific mechanical properties and are cost-effective. Based on this, the present study aims to determine the impact resistance of polyester matrix composites reinforced with sisal and jute fibers through Charpy impact tests. The fibers were used as acquired, without surface treatment, under environmental conditions, and cut to a length of 15 mm. The specimens were manufactured by manual molding (hand lay-up) using silicone molds and without pressure. The impact tests were carried out on specimens reinforced with discontinuous and randomly oriented fibers, for mass fractions varying according to the volumetric capacity of the mold. The absorbed energy increased from 31.50 kJ/m2 for the unreinforced polyester to 78.16 and 78.13 kJ/m2 for the sisal and jute reinforced composites, respectively. To statistically validate the level of reliability and significance of the Charpy impact test results, Weibull analysis was performed. Furthermore, a fractographic analysis was carried out using scanning electron microscopy (SEM) to analyze in detail the fracture surfaces of the tested samples and understand the failure mechanisms of each material.