PENGARUH PULLING SPEED DAN DURASI PERENDAMAN SERAT KARBON DALAM LIQUID NITROGEN TERHADAP FLEXURAL PROPERTIES KOMPOSIT SERAT KARBON BERMATRIK POLYPROPYLENE

Fiber-reinforced composites have received great attention from researchers and scientists around the world, have been widely used for various applications such as aerospace, automobile, civil infrastructure, and marine. A composite material that combines two or more materials as a matrix with different properties with the aim of getting better material properties than a single constituent material. The advantages of composite materials include light weight, strength, corrosion resistance, flexibility and low wear rates. The purpose of this study was to determine the effect of carbon fiber immersion duration and tensile speed on the flexural properties of specimens with variations, and to find the optimal combination of process parameters of flexural properties in carbon fiber reinforced composites. The initial process are to prepare tools and materials. Then do the immersion of carbon fiber in liquid nitrogen with time variations of 10, 15, and 20 minutes. After that, making a composite filament using an extrusion-pultrusion machine with variations in the tensile speed of 38,40,42 cm/minute. The composite filament obtained was then cut according to the mold then the printing process was carried out using a hot press machine at a temperature of 195 oC. Bending testing is carried out in order to obtain the value of flexural properties with specimen dimensions of 40 mm x 10 mm x 1 mm. The results showed that the most influential factor on the bending strength for carbon fiber reinforced composites was tensile speed. The faster pulling speed is able to distribute the load evenly. The immersion time did not have much effect on the results of flexural strength as shown by the value of 11.605% and the flexural modulus of 13.366%. The combination of the most optimal level of process parameters on flexural strength and flexural modulus has the same level, namely immersion time of 20 minutes and tensile speed of 42 cm/minute.