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This paper explains the successful and simple process of generating a rubber mount with novel properties by incorporating carbon black particles type ISAF 220 at different ratios ([46, 56, 66, 76, 86] [pphr]). Rubber mounting was made using 100 % natural rubber and carbon powder that was applied to the master batch ratio (60 g). To achieve greater homogeneity, rubber and carbon were combined for several minutes. The rubber mount has been subjected to several tests at Babylon tires factory and Babylon University (tensile, elongation, modulus, compression, hardness, rebound resilience, specific gravity and fatigue tests). The best results were obtained from the rubber mount, as it had the ability to resist fatigue and could be used for a long period of time. It could also increase the number of cycles to 900 rpm. The rubber mount that was reinforced with carbon had a better resistance to the mechanical properties (tensile, hardness, fatigue and resilience). The results of the tensile strength, hardness, fatigue and resilience tests showed that additional quantities of carbon at 66 pphr increased the values by up to 18.95 Mpa, 64 Mpa, 600 Mpa and 55.5 Mpa, respectively.

A numerical study using the ANSYS 19.R3 environment is discussed in this research. This environment depends on the Virtual Crack Closure Technique (VCCT) method to test a double cantilever beam (DCB) according to the ASTM D5528 standard. Four kinds of laminate stacking sequences were considered. According to the results, the distribution of the strain energy release rates obtained along the delamination front in bending-extension and extension-twisting coupling had a good affinity with bending-extension coupling. At the same time, critical fracture toughness values were estimated to be around 87.9% of critical fracture toughness values bending-extension coupling. These results are proof of the bending-extension and extensiontwisting coupling success while testing the proximity to bending-extension coupling results of the DCB beam. These findings are compatible with the standard ASTM D5288. Therefore, the bending-extension and extension-twisting coupling provide a good indication of the delamination resistance during buckling tests of the composite.

Self-healing materials possess the capacity to repair or mend themselves either by inherent response or under external stimuli and one of the most important approaches in self-healing is encapsulation. In this study, poly methyl methacrylate (PMMA) microcapsules containing epoxy resin and amine hardener have been successfully synthesized via solvent evaporating technique with core/shell ratio of 1:1, agitation speed 500 rpm, temperature of 40 °C and 3% wt. of surfactant concertation. The synthesized system is binary for self-healing anti-corrosion coating purposes. Fourier-transform infrared (FTIR), field emission scanning electron microscope (FESEM), Optical microscope (OM), Differential scanning calorimetry (DSC), and Thermal gravimetric analysis (TGA) were used to characterize the microcapsules and monitor the healing process. A corrosion resistance test has been done for a stainless steel substrate after coated with epoxy mixed with four percentages (0, 10, 15, and 20 wt. %) of equal quantities from prepared microcapsules (resin/hardener). The results showed that the corrosion of the coated specimen decrease with increasing microcapsules percentage which indicates that the self-healing system worked successfully.

This paper investigates the effect of the nanoparticle SiO2 on the mechanical and physical properties of a rubber blend of natural rubber (NR) and styrene-butadiene rubber (SBR). The proportions of the nanoparticle that are added are 0, 0.2, 0.4, 0.8, 1, 1.5, 2, 2.5 and 3 pphr to a fixed percentage of rubber blend (30% NR/70% SBR), which has been prepared with vulcanisation factors, accelerators and activators using a two-roll mill laboratory, moulds and a thermal piston; the pressure, temperature and time difference test conditions according to standards. The results of the laborator tests show an increase in the mechanical properties (i.e. tensile strength, modulus of elasticity, resilience and tear resistance) with increases in the percentage load (pphr) until 0.8 pphr, which is when there is a slight decrease; the properties of hardness, fatigue and compression set also increase. While the results for the physical properties show an increase in viscosity, the greater torque, scorch and cure times decrease with increases in the proportion of SiO2 in the rubber recipe.

In this work, functionally graded materials were synthesized by centrifugal technique at different volume fractions 0.5, 1, 1.5, and 2% Vf with a rotation speed of 1200 rpm and a constant rotation time, T = 6 min . The mechanical properties were characterized to study the graded and non-graded nanocomposites and the pure epoxy material. The mechanical tests showed that graded and non-graded added alumina (Al2O3) nanoparticles enhanced the effect more than pure epoxy. The maximum difference in impact strength occurred at (FGM), which was loaded from the rich side of the nano-alumina where the maximum value wasat 1% Vf by 133.33% of the sample epoxy side. The flexural strength and Young modulus of the functionally graded samples were enhanced by 43.69% and 52.74%, respectively, if loaded from the alumina-rich side. On the other hand, when loading (FGM) from the epoxy side, the amount of decrease in bending resistance was 122.4% while the improvement in bending modulus was 81.11% compared to pure epoxy. Scanning electron microscopy (SEM) revealed the fracture surface of the impact samples and the gradient scattering of nanoparticles in the epoxy matrix. Numerous applications can be used to manufacture the functionally graded material by centrifugal casting method, including for the manufacture of gears and all bending applications such as leaf springs.

Currently, personal armor is considered the basic requirement in combat, especially in the Middle East. The current research attempts to design and manufacture a novel body armor from cheap and available materials. When compared to traditional materials’ body armor, composite ballistic body armor has become a superior alternative for personal protection. In this study, alternative materials were proposed to develop an armor consisting of modified rubber and ebonite, as well as pieces of ceramic from alumina as hexagons shape, Kevlar and Carbon woven, and modern technologies shear thickening fluids. The armor was numerically evaluated using (ANSYS) commercial software using different bullet velocities ranging from (740 to 940) m/s and different numbers of carbon and Kevlar woven soaking shear thickening fluids to reach the best arrangement of layers with the best performance and compare them in the experimental data. The numerical results show the best performance for plate armor consisting of 23-layers, which were then experimentally tested using a weapon type (AK-47) rifle with bullet 7.62*39 mm. The experimental test showed no complete penetration, with a back deformation of 7.5 mm. When the shock of the double bullet into the plate at the same location showed no complete penetration with a back deformation of 11.3 mm, the body armor exhibited superior protective performance and was compatible with standard NIJ Standard-0101.03.

In this work, functionally graded materials were synthesized by centrifugal technique at different volume fractions (0, 0.5, 1, 1.5, and 2% Vf) with different rotational speed of (0, 600, 800, 1000 and 1200) r.p.m and different rotational time (0, 1, 2, 3 and 4) min. The hardness and tribological properties were characterized to study the graded and non-graded nanocomposites and the pure epoxy material. Using a pin-on-disc machine, sliding wear tests are conducted with the following parameters: rotation speed (400 rpm), normal load (30 N), filler content (0–2% Vf), and sliding distance (0.15 km). The hardness and wear parameters of graded composites were investigated and compared to those of epoxy composites with homogeneous filling. This work demonstrates that incorporating Al2O3 nanoparticles improves graded composites' hardness and sliding wear resistance. Epoxy–Al2O3 epoxy composites with a volume fraction of 2 had the lowest specific wear rate of all samples. The FGMs had superior sliding wear performance compared to homogenous composites. The maximum difference in hardness and coefficient of friction occurred at (FGM), which is loaded from the rich side of the nanoalumina at (Vf = 2%, N = 1200 r.p.m and T = 6 min), where the maximum value was 168% and 78 % as compared with neat epoxy, respectively. The wear rate of the functionally graded samples was enhanced by (87.7%) compared with neat epoxy if loaded from the alumina-rich side.