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چکیده
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This thesis involves Study and Evaluation of the effect of adding partials of rubber as these materials are cheap and available and can be obtained from the raw material for the tire industry and some other usages. an extensive experimental and numerical work were conducted, this involves dispersed them with different weight fractions such as 2, 4 and 8 wt. % with using a control without adding any rubber particles (0%), this is termed as an elegant. This process was performed using processing of polymers hand layup methods (HLM). (CM)- under investigation were then prepared by reinforcing the resulting composite with Three layers of carbon fiber that go in both directions. referred to as cross-ply symmetric (0-90) W Fibers were hand-laid up to make the angles. here the rubber was mixed with the epoxy binder, it was mixed well and a good distribution was obtained between the strands of the fibers. The required testing specimens then were prepared according to (ASTM) standards. Different mechanical and dynamic tests were conducted such as tensile, flexural, impact Hardness Tests, free vibration tests, and Morphology properties SEM. A free vibration test was carried out to investigate the impact of (MPR) on the damping ratio and frequency response., of (CM). The numerical analysis incorporating using integrated within ANSYS 2020 (APDL-BEAM188) for modeling free vibration test. The obtained results through the numerical work were verified with those obtained from experimental tests. Experimental results, demonstrated that an increase in the (MPR) weight fraction resulted in a corresponding rise in the (CM) damping ratio from (0.0321 at 0 wt.%) to (0.0714 at 8wt.%), while the natural frequency increased also from (16 Hz at 0%) up to (21Hz at 8%) at (wt.%) of MPR. Then the natural frequency decreased to (Hz) for the UP reinforced with (wt.%) of (MPR). The Importance of Hardness Tests in giving a quick detection of changes in the mechanical properties of the material as a result of manufacturing. A "Shore-D". When designing the sample thickness of the sample tested (6 mm) equal to (78.55), it is very close to the results of other samples with a thickness of (4mm). The hardness of the composites was higher for (EP/CCC/0%MPR), than for the same composite with MPR. They also showed that, the highest hardness was for composites without MPR. The results were from (71.866 at 0%MPR) into (69.866 at 8%MPR). In this context, a gradual decrease in hardness was observed. Impact Test: was used to evaluate the tolerance range of (CM) to impact force by absorption of energy. The impact test differs from other mechanical tests in that the specimen was subjected to rapid stress, leading to changes in the materials response. The increase in results was gradual; the results were from (7.55 kJ/m² at 0 wt.%), decreases to (5.993 kJ/m² at 2 wt. %), Where we notice the increase starting from (11.573 kJ/m² at 4wt.%) to (23.955 kJ/m² at 8 wt.%). The impact strength for the sequence of layers laminated composite increases by about (74.9%) when adding (MPR). Bending method was used to evaluate the bending strength and hardness of an in (CM). In bending test, the specimen was loaded horizontal in a 3-point- load configuration. The findings in the two specimens (2, 4 wt.% MPR) were lower than in the specimen without addition, but the percentage of rubber in the specimen was increased to (8%). The first specimen value was (73.326 at 0wt.%), dropped to (67.524 and 65.769 at 2wt.% and 4wt.%), then increased to (108.416 at 8wt.%). The flexural modulus of such composites increased from (1250.692MPa) for neat UP to (3166.182 MPa) for UP reinforced by from (4wt.% to 8% wt. %) of (MPR), representing a (60%) increase., when (MPR) particles with (8% wt.) were added to composite material, the flexural modulus of such materials rose. reduce the bending modulus of the sequence of layers (2wt.%) laminated roughly (44%) when compared to (0wt.%) laminated composite, while it becomes (47%) (4wt.%) composite respectively. Tensile Test, the main results of such a test which was obtained from the device. Using the tensioning device and the graph it offers (load / deformation), a greatest stress at the ratio (181.25MPa at 2wt.%), was firstly noticed and then, according to the schematic, where (162.5MPa at 0wt.%) and (143.75MPa at 4wt.%) sequentially until (109.375MPa at 8wt.%). The modulus of elasticity was determined by the devise, and according to the given design and calculations, the maximum value (5.225 Gpa at 8wt.%), was recorded, followed by values of (3.55 Gpa at 4wt.% and 3.42 Gpa at 2wt.%) compared to the sample that contains no rubber particles followed by value (3.598 GPa at 0wt.%mpr). The SEM technique was used for morphological study of the investigated samples to probe the microstructure of the failed specimen during impact test, it's clear that, (500X-925X - Zoom power) shows the total fracture phase of the whole specimens Laminate.
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