Iranian Journal of Materials Science and Engineering

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The presence of alloying elements, sometimes in a very small amount, affects mechanical properties one of these elements is Boron. In Aluminum industries, Boron master alloy is widely used as a grain refiner In this research, the production process of Aluminum –Boron master alloy was studied at first then, it was concurrently added to 2024 Aluminum alloy. After rolling and homogenizing the resulting alloy, the optimal temperature and time of aging were determined during the precipitation hardening heat treatment by controlled quenching (T6C). Then, in order to find the effect of controlled quenching, different cycles of heat treatment including precipitation heat treatment by controlled quenching (T6C) and conventional quenching (T6) were applied on the alloy at the aging temperature of 110°C. Mechanical properties of the resulting alloy were evaluated after aging at optimum temperature of 110°C by performing mechanical tests including hardness and tensile tests. The results of hardness test showed that applying the controlled quenching instead of conventional quenching in precipitation heat treatment caused reduction in the time of reaching the maximum hardness and also increase in hardness rate due to the generated thermo-elastic stresses rather than hydrostatic stresses and increased atomic diffusion coefficient as well. Tensile test results demonstrated that, due to the presence of boride particles in the microstructure of the present alloy, the ultimate tensile strength in the specimens containing Boron additive increased by 3.40% in comparison with the specimens without such an additive and elongation (percentage of relative length increase) which approximately increased by 38.80% due to the role of Boron in the increase of alloy ductility

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B4C–Al2O3 composite powder was produced by aluminothermic reduction in Al/B2O3/C system. In this research, microwave heating technique was used to synthesize desired composite. The ball milling of powder mixtures was performed in order to study the effect of mechanical activation on the synthesis process. The synthesis mechanism in this system was investigated by examining the corresponding binary sub-reactions. The self-sustaining reduction of boron oxide by Al was recognized to be the triggering step in overall reaction.

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In this study, Boron carbide was synthesized using Mesoporous Carbon CMK-1, Boron oxide, and magnesiothermic reduction process. The Effects of temperature and magnesium grain size on the formation of boron carbide were studied using nano composite precurser containg mesoporous carbon. Samples were leached in 2M Hydrochloric acid to separate Mg, MgO and magnesium-borat phases. SEM, XRD and Xray map analysis were caried out on the leached samples to characterize the  boron carbide. results showed that the reaction efficiency developed in samples with weight ratio of B₂O₃:C:Mg = 11:1.5:12, by increasing the temperature from 550 to 650 °C and magnesium powder size from 0.3 m to 3 m.

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The boronizing of a tungsten heavy alloy containing Ni and Fe as the major alloying elements were performed in the present study to increase its surface hardening. Pack cementation method was employed as a well-known, successful solid-state process for boronizing. The coating treatment was accomplished at different temperatures of 1000, 1050 and 1100°C for 6 and 9 hours. The formation of tungsten boride phase was confirmed, although a silicide layer covered the surface of the specimen as the outer layer. The mechanism of the formation of a multilayered surface was explained. The maximum thickness of reaction zone and surface hardness achieved in the current work were 300 µm and 2470 HV, respectively.

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Hybrid composite finds wide application in various fields. In this present study, the hybrid composites are developed using stir casting technique as per Taguchi’s L9 orthogonal array. Hybrid composites were fabricated using Aluminium Al6082 as the base material and reinforced with the combinations of reinforcements Al2SiO5 and B4C at three levels (4%, 8% and 12%).The developed composites were analyzed for micro structural  investigations and mechanical tests were done as per ASTM standards. The micro structural analysis was done using optical Microscope and Scanning electron microscope while composition studies were done using X-ray diffraction and EDAX. Mechanical test like tensile, impact and flexural were conducted and their damage assessment was done using Scanning electron microscope. The fatigue characteristics like high cycle fatigue and fatigue crack propagation was studied both experimentally and numerically. The experimental data and numerical modeling analysis data obtained for the hybrid composite system, agree with each other.           

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Considering the widespread use of aluminum composites in various industries and the emergence of nanomaterials such as graphene and boron nitrite (BN) with their unique properties, aluminum-based nanocomposite reinforced by the graphene-BN hybrid was fabricated at different percentages. For this purpose, the graphene-BN hybrid was prepared and subjected to wet milling along with the aluminum powder. The mechanical properties of the final nanocomposite which was consolidated using the spark plasma sintering (SPS) method were examined. Aluminum-based composite specimens containing 1 wt.% graphene–0 wt.% BN (AGB1), 0.95 wt.% graphene–0.05 wt.% BN (AGB2), 0.90 wt.% graphene–0.1 wt.% BN (AGB3), and 0.85 wt.% graphene–0.15 wt.% BN (AGB4) were fabricated and compared with non-reinforced aluminum (AGB0). The hardness values of 48.1, 51.1, 56.2, 54.1, and 43.6 Hv were obtained for AGB0, AGB1, AGB2, AGB3, and AGB4, respectively. Additionally, tensile strengths of these specimens were 67.2, 102.1, 129.5, 123.7, and 114.7 MPa, respectively. According to the results of the hardness and tensile tests, it was revealed that the AGB2 specimen had the highest tensile strength (93% higher than AGB0 and 27% higher than AGB1) and hardness (17% higher than AGB0 and 10% higher than AGB1).

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In this study, zinc chloride (ZnCl) was used as a precursor chemical to form boron reinforced zinc oxide (ZnO:B) particles. The supercapacitor performance of the reduced graphene oxide/boron reinforced zinc oxide (RGO/ZnO:B) composite electrodes produced by hydrothermal methods, and the impact of different boron doping ratios on the capacitance, were both examined. The characterization of the RGO/ZnO:B composites containing 5%, 10%, 15% and 20% boron by weight were performed using X-Ray diffraction (XRD) and scanning electron microscopy (SEM). The capacitance measurements of the electrodes produced were conducted in a 6 M KOH aqueous solution with a typical three electrode setup using Iviumstat potentiostat/galvanostatic cyclic voltammetry. The specific capacitance value of the 20% reinforced RGO/ZnO:B composite electrode was 155.88 F/g, while that of the RGO/ZnO composite electrode was 36.37 F/g. According to this result, the capacitance increased four-fold with a 20% boron doping concentration. Moreover, a longer cycle performance was observed for the RGO/ZnO:B electrodes with higher boron doping concentrations.