OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 25 No. 3 2023 mat was placed inside the resin, and with the aid of a roller, the resin was distributed over the mat. This process was then repeated for a four-layered mat before the cavity was filled with the calculated amount of resin. A compression moulding machine is then used to compress the mould, curing it for an hour at a temperature of 80 °C and a pressure of 150 kgf/cm2. The obtained composite laminates were sliced to prepare specimens in accordance with ASTM specifications. Fig. 2 and 3 respectively depict the compression moulding machine setup and composite preparation. According to ASTM D-638 standard, a tensile test was performed at a testing speed of 2 mm per minute. The dog bone shaped sample had the following dimensions: length 165 mm, gauge length 57 mm and width 13 mm. Flexural tests using three-point bending were conducted in accordance with ASTM D-790 standards at a testing speed of 1.7 mm per minutewith position accuracy 0.001 mm and speed accuracy 0.005 % uses for testing. Specimen was made with standard dimensions: 127 mm in length, 12.7 mm in width and 4 mm in thickness. The impact test on the 63.7 × 12.7 ×3 mm composite specimen followed the recommendations of ASTM D-256 with an angle accuracy of 0.1°. Fig. 1. Basket weave jute fibers Fig. 2. Composite preparation flow diagram Analysis of free vibrations has allowed researchers to better understand the dynamic behavior of composite materials. Using experimental modal analysis, the natural frequency and associated damping factor of the composite was found. Experimental modal analysis is performed using the impulse hammer test. Fig. 4 shows a diagram of the impulse hammer test. For this analysis, the first three bending modes of the composite made of basket-woven jute fiber have been taken into account. The investigation of free vibrations was done in a free-free environment. A sample with dimensions of 170 × 17 × 3 mm was mounted on a rigid end support such as a cantilever beam and a 4 gram light accelerometer was positioned over the sample to obtain the first three natural frequencies of the woven jute fiber composite. Utilizing a lightweight accelerometer helps to avoid additional impact on the mass of the woven composite. After the impulse, the impact signal is sent to an 8-channel DEWE data acquisition system to use the fast Fourier transformation algorithm (FFT Algorithm) to convert the time domain signal to frequency form. Direct measurements of the relevant damping factor values may be made with the DEWE data gathering system.Depends upon the frequency response resonance peak initially three peaks have been clearly visible and corresponding to
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