Evaluation Of Mechanical Performance Research Articles

Molecular mechanism and extraction performance evaluation of choline chloride-based deep eutectic solvents for phenol separation from oil: Different glycols as hydrogen bond donors

Highly efficient separation of phenols from coal-to-liquids can enhance the economics of the coal conversion process. The selection of extractants with high extraction efficiency and low neutral oil entrainment is significant for energy development strategy. In this study, four ChCl-based DESs with different glycols as hydrogen bond donors (HBDs) were designed for the separation of phenol/toluene mixtures and the experimental results were analyzed by theoretical calculations. The experimental results showed that ChCl-EG had the highest extraction efficiency (94.02 %) and the least entrainment of toluene (0.449 g). Meanwhile, it could be regenerated and reused four times with no significant change in extraction capacity. The formation of hydrogen bonds between DESs and phenol was elucidated by σ-profile based on COSMO-SAC model. Multi-scale simulations and comparative analyses of the micro-mechanisms of the DESs system were carried out using quantum chemical (QC) and molecular dynamics (MD). It was shown that the attraction of DESs to phenol was mainly due to hydrogen bonds and vdW forces, with hydrogen bond interaction between Cl− in ChCl and H atom in phenol hydroxyl group being dominant. As the chain length of HBDs increased, the interaction of DESs with phenol was enhanced, while the entrainment of toluene also increased. Overall, the effect on the separation of phenol by different chain lengths of glycols as HBDs is elucidated. This study provides a theoretical reference for selecting and designing other DES extractants to separate phenol/toluene systems and similar systems.

Effective Utilization of Bast Fiber in High Density Polyethylene Nanocomposite Enriched by Alumina Nanoparticle: Mechanical Performance Evaluation

Effective Utilization of Bast Fiber in High Density Polyethylene Nanocomposite Enriched by Alumina Nanoparticle: Mechanical Performance Evaluation

Role of customized scan strategies and dwell time on microstructure and properties of additively manufactured 316L stainless steel

Direct energy deposition (DED)-based additive manufacturing facilitates fabrication of medium-to-large functional parts. This study assesses the role of varying scan strategies and dwell time between each layer to control the cooling rate of 316L stainless steel produced by the laser-engineered net shaping-DED method. Customized print patterns were designed, keeping other optimized print parameters constant to obtain printed parts with better dimensional tolerance. The parts, which were >99% dense, were fabricated in a controlled argon environment. A heterogeneous microstructure consisting of a cellular columnar and equiaxed substructure was obtained. Two-dimensional X-ray diffraction revealed the presence of a single-phase γ-austenitic FCC phase. A refined microstructure with less elemental segregation was noticed with an increase in dwell time between the print layers. Internal defect analysis using X-ray micro-computed tomography revealed low lack-of-fusion voids along the build direction without any micro-cracks, which is attributed to higher cooling rates between subsequent print layers. As demonstrated in a mechanical performance evaluation of tensile and micro-hardness properties, better performance can be achieved by controlling the cooling rate and customizing deposition patterns.

The Development of Sustainable Polyethylene Terephthalate Glycol-Based (PETG) Blends for Additive Manufacturing Processing-The Use of Multilayered Foil Waste as the Blend Component.

The polymer foil industry is one of the leading producers of plastic waste. The development of new recycling methods for packaging products is one of the biggest demands in today's engineering. The subject of this research was the melt processing of multilayered PET-based foil waste with PETG copolymer. The resulting blends were intended for additive manufacturing processing using the fused deposition modeling (FDM) method. In order to improve the properties of the developed materials, the blends compounding procedure was conducted with the addition of a reactive chain extender (CE) and elastomeric copolymer used as an impact modifier (IM). The samples were manufactured using the 3D printing technique and, for comparison, using the traditional injection molding method. The obtained samples were subjected to a detailed characterization procedure, including mechanical performance evaluation, thermal analysis, and rheological measurements. This research confirms that PET-based film waste can be successfully used for the production of filament, and for most samples, the FDM printing process can be conducted without any difficulties. Unfortunately, the unmodified blends are characterized by brittleness, which makes it necessary to use an elastomer additive (IM). The presence of a semicrystalline PET phase improves the thermal resistance of the prepared blends; however, an annealing procedure is required for this purpose.

Enhancing powder bed fusion of alumina ceramic material: a comprehensive study from powder tailoring to mechanical performance evaluation

Powder bed fusion (PBF) is an additive manufacturing (AM) technique that holds a great promise for alumina ceramic materials to be processed in a one step. To ensure an effective outcome, the powder material should be thoroughly tailored, and the process parameters should be appropriately investigated. These process parameters include laser power, scanning speed, hatching space, and scanning strategies. The alumina powder has been tailored and modified to be appropriately used for PBF using the spray-drying technique, and the process parameters have been predicted and selected using a developed numerical model. Different scanning speeds of 100, 200, 300, and 400 mm/s have been considered, and the other parameters have been numerically predicted. The results demonstrated that spray drying is an effective technique for tailoring the characteristics of alumina powder, such as particle shape, particle size distribution, flowability, and absorptivity, making it ideally suited for PBF processing. Furthermore, the developed numerical model demonstrated outstanding reliability in predicting the most effective laser power and hatching space for different scanning speeds, resulting in significant cost and time savings when compared to relying solely on experimental trials. Employing a scanning speed of 400 mm/s yielded a significant improvement in relative density and quality of the printed samples surpassing other scanning speeds. Moreover, this speed effectively addressed various challenges encountered by other scanning speeds. Following the optimization of process parameters, it was determined that a relative density of 94.5% could be achieved by utilizing a scanning speed of 400 mm/s, a laser power of 210 W, and a hatching space of 30 µm. However, the evaluation of mechanical performance revealed that while the microhardness of the printed alumina samples matched the values reported in the literature, the attained compressive strength fell significantly below the values reported in the literature.

Evaluation of mechanical performance, corrosion behavior, texture characterization and aggressive attack of OPC-FMK blended cement pastes modified with micro Titania

Building constructions are vulnerable to a major financial loss due to the dangerous degrading process of steel corrosion in reinforced concrete, which requires frequent repairs. This study examined the durability of steel cement-based covers and steel corrosion in two severe media, NaCl and MgSO4. The degree of penetration of these harmful ions was determined by monitoring the mechanical properties and porosity profile (using the N2-adsorption/desorption technique) of cement-based steel covers made from OPC and fine metakaolin (FMK) reinforced by micro-titania (MT). Additionally, after the immersed steels were exposed to solutions containing 7% NaCl and 7% MgSO4 for four months, the steel corrosion rates (CR, mpy) were assessed. The results demonstrated that blending OPC by FMK up to 30% could develop mechanical properties similar to plain OPC at later hydration periods of 28 and 90 days. XRD and TGA/DSC analyses connected this behavior to the emergence of novel phases, namely strätlingite and hydrogarnet, in OPC/FMK combinations. Better mechanical performance was demonstrated by blended mixes containing between 1% and 3% MT in all curing media. The replacement of OPC with 30% FMK in the presence of 3% MT resulted in significant changes in the porous system from macro to meso-nature, as confirmed by the BET and BJH models. Under normal, sulphate, and chloride curing, respectively, the maximum pore diameters (dpmax) decreased by 66.19%, 78.40%, and 79.14%. When CSH clusters were observed under a scanning electron microscope (SEM), they seemed to be symmetrical and organized, similar to floral crystals. This development is partially attributed to micro TiO2. Based on CR values, it was found that steel corrosion was higher in MgSO4 solutions than in NaCl solutions. Steel coverings made of OPC/FMK composites with 3% MT were able to reduce CR by 65.8% in MgSO4 solutions and by 56% in NaCl solutions.

Study of molecular mechanism and extraction performance evaluation for separation of phenolics from alkaline wastewater through synergistic extraction

ABSTRACT Phenols were a kind of pollutant in coal chemical wastewater with high concentration and difficult to decompose and have a significant impact on the subsequent biochemical treatment of the wastewater. In addition, phenols were a kind of weak electrolytes that partially dissociation oxidation under weakly alkaline conditions, making recovery more difficult. In order to solve this problem, phenols were extracted from weak alkaline wastewater with a synergistic solvent. First, the interaction between solvents and phenols and the solvent effect of solvents were calculated by quantum chemistry and the synergistic extractant cyclohexanone/1-pentanol was determined to have significant advantages. Moreover, the synergistic extractant was further analyzed through independent gradient model based on Hirshfeld partition analysis, atoms in molecule topology analysis, electrostatic potential analysis. Results indicated that the synergistic extract can provide multiple hydrogen bond interactions with phenol due to the double action sites of the C=O group of ketone and the -OH group of alcohol. In addition, the efficacy of the extractant was validated by multistage extraction, indicating partial dissociation oxidation of hydroquinone to benzoquinone under weakly alkaline conditions, with removal rates of 99.5% and 99.2% for phenol and hydroquinone, respectively. In general, the synergistic extractant can effectively remove phenols.

Systematic approach to improve overlap laser welding of AA5052-H32 with dissimilar thickness by evaluation of mechanical performance, undercut, and welding penetration

Systematic approach to improve overlap laser welding of AA5052-H32 with dissimilar thickness by evaluation of mechanical performance, undercut, and welding penetration

Evaluation of Mechanical Performance and Antibacterial Efficacy of Alumina‐Silver Nanoparticle‐Reinforced Bioepoxy for Dentistry

The lack of mechanical and antibacterial characteristics of most dental resins impedes their broader applications in dentistry. Therefore, this study aimed to enhance biocompatibility and mechanical and antibacterial features of bioepoxy (BE) to be used in dentistry. The properties of BE were assessed prior to and after reinforcing with several loading of nanoalumina (Al2O3)/nanosilver (AgNPs) particles. The mechanical characteristics were evaluated using three‐point bending and Izod impact tests. The morphologies and surface roughness of pristine BE and nanoalumina/nanosilver‐reinforced BE composites were observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. The influence of these additives on the BE antibacterial properties were evaluated using the agar diffusion approach. The flexural strengths of the modified BE composites with nanoalumina/nanosilver particles were higher than those for additive‐free BE, and their values were considerably dependent on filler loading. The impact strength and flexural strength of composite materials were greater at hybrid reinforcement loading of 2 wt%. At such ratio, an increase of approximately 33.8% was obtained in the flexural strength compared with that of blank BE. On the other hand, the incorporation of higher proportions of nanoparticles led to a decrease in overall properties of composites, yet they were higher than that of additive‐free BE. The flexural strength for the composite containing 0.5 wt% AgNPs and 3.5 wt% Al2O3 was higher than the value stated for the nanoparticles‐free BE by 18.7%. Furthermore, the composite comprising 0.5 wt% of each of the nanoparticles had a great ability to alleviate the spreading of Staphylococcus aureus and Escherichia coli when compared with the resin and composites with other formula. For instance, the diameter of inhibition zone (DIZ) against Staphylococcus aureus of the aforementioned composite increased about 16% than that of additive‐free BE. All these features make this composite system a promising candidate in biomedical applications especially in dental related applications.

Blockchain-based E-commerce Transaction Verification Mechanism Design and Performance Evaluation

Abstract With the development of blockchain technology and the increased demand for its application in e-commerce. However, the encryption algorithm of traditional blockchain technology poses a risk to data security protection. Therefore, this paper builds secure cryptographic protection by means of secondary encryption and interactive verification of the interaction process of e-commerce transaction data through a hash function. Then, for the transaction process of e-commerce, an electronic transaction protocol with privacy protection is proposed. The effectiveness of blockchain-based e-commerce transactions is analyzed according to correctness and security. The questionnaire of this study has good reliability based on the analysis of relevant data, where the overall reliability of all variables is 0.865. There is a positive correlation between the efficacy of e-commerce transactions and correctness, anonymity, resistance to simulation attacks, and accountability protocols at the 5% significance level. The correlation between traceability, non-repudiation, and resistance to replay attacks is not significant. E-commerce transaction effectiveness = 0.326* correctness + 0.455* anonymity + 0.354* traceability + 0.254* non-repudiation + 0.171* resistance to simulation attacks + 0.445* resistance to replay attacks + 0.552* accountability protocol. The accountability protocol factor has the greatest impact and contribution to the e-commerce transaction effectiveness of blockchain.

Evaluation of Mechanical Performance of Asphalt Emulsion Stabilized Base Course Composed of Reclaimed Asphalt Pavement and Asphaltenes

Abstract Reclaimed asphalt pavement (RAP) is a material that is produced by milling old asphalt pavement that can be mixed with virgin asphalt binder and aggregates to fabricate a recycled asphalt mixture. Using RAP in pavement structure can promote sustainability and reduce construction costs. In this study, asphaltenes, which is a waste material derived from oil sands deasphalting operation, was added as a modifier to recycled mixtures composed of different contents of RAP. A proctor test was conducted to determine the optimum fluid contents. Mix designs were performed for mixtures with 50 %, 75 %, and 100 % RAP with asphalt emulsion and different asphaltenes contents. Mechanical properties of the modified mixtures were evaluated by conducting the indirect tensile strength (ITS) test, creep compliance and strength test, indirect tensile asphalt cracking test (IDEAL-CT), and Hamburg wheel tracking test. The optimum emulsion content was determined to be 1.5 % based on sample performance using the ITS test. The results indicate that asphaltenes improves the strength up to the design-specified limits. The asphaltenes-modified samples show lower creep compliance and fracture energy (FE) values than the unmodified sample, indicating these samples are potentially more prone to cracking. Further, statistical analysis shows the difference in FE is significant at the lowest testing temperatures (−20°C). Asphaltenes-modified mixtures have greater cracking resistance at the intermediate temperature (25°C) and rutting performance at high temperature (40°C) than the unmodified mixture. However, based on FE and rutting resistance index, the improvements are not significant. Overall, the 100 % RAP mix with 1 % asphaltenes had the best tensile strength, cracking resistance, rutting resistance, and low temperature properties compared to other modified mixes.

Sustainable Composite of Cardanol Based Phenalkamine Cured Epoxy Systems: Fabrication, Characterization and Mechanical Performance Evaluation for Emerging Applications

Sustainable Composite of Cardanol Based Phenalkamine Cured Epoxy Systems: Fabrication, Characterization and Mechanical Performance Evaluation for Emerging Applications

Experimental Study and Numerical Analysis of Temperature Stress in Carbon Fiber-Heated Concrete Pavement

Carbon fiber heating technology has been widely used in pavement surfaces in practical engineering projects as an environmentally friendly, efficient, and safe ice melting technique. However, the current design of carbon fiber-heated pavement focuses primarily on the ice melting effect while neglecting the crucial mechanical performance evaluation. Therefore, this study aims to investigate the temperature and thermal strain distributions of concrete pavement through model tests and develop a corresponding three-dimensional numerical model to analyze the temperature stress field distribution of carbon fiber-heated pavement. The accuracy of the numerical model is verified by comparing the model test results with the numerical analysis results. The numerical model test results indicate that the maximum compressive stress near the carbon fiber wire is 4 MPa, while the maximum tensile stress between the two carbon fiber wires is 1 MPa. According to the design standard for highway cement concrete pavement, the temperature stress induced by temperature change is significantly lower than the design value of the material’s inherent strength. In addition, a linear relationship between the depth and temperature gradient affecting temperature stress is observed after establishing a correlation between the temperature gradient and temperature stress. The findings of this study can provide valuable insight into the design of carbon fiber-heated concrete pavements.

Experimental and numerical evaluation of mechanical performances of hybrid Palmyra-Palm-Leaf-Stalk/Glass fiber reinforced polyester composites

In the present work, four layered Palmyra-Palm-Leaf-Stalk (PPLSF)/Glass hybrid composites laminates with six distinct stacking orders were made by following hand lay-up method. Different experiments were carried out to determine the tensile, flexural, impact and hardness of the laminates as per ASTM standard. The results reveal that the addition of glass fiber to PPLSF significantly enhanced the mechanical performance of the laminates. On successive replacement of PPLSF by glass fiber, an enhancement of properties such as 291.39% for tensile strength, 72.08% for flexural strength, 75.82% for impact strength, and 78.44% for micro-hardness was observed. Again, it is also noticed that the stacking order plays an important role in influencing the properties while comparing experimental finding of laminates with equal weight percentages PPLSF and glass fiber. Further to perform Finite Element Analysis (FEA), a 3D CAD model of tensile and flexural specimen was created in space-claim modeler of ANSYS R19.0 and subsequently imported to generate numerical predicted values. While comparing the numerical and experimental results, there was very good agreement among the results was found. Scanning Electron Microscope (SEM) was used for fractography analysis of the tested samples to examine the different mode of failures.

Mechanical properties and performance evaluation of aluminum nickel phosphorus bronze MMC reinforced with TiCN + SiC nanopowders for lightweight armored vehicles

Mechanical properties and performance evaluation of aluminum nickel phosphorus bronze MMC reinforced with TiCN + SiC nanopowders for lightweight armored vehicles

1 experimental and numerical evaluation of residual mechanical performance of carbon/epoxy laminated coupons after integration of solid battery cells for aeronautical applications

The present study deals with a numerical and experimental evaluation of the residual mechanical performance of a quasi-isotropic carbon/epoxy laminated composite plate in which solid battery cells have been integrated. Firstly, the mechanical properties of the multifunctional Reinforced Multilayer Stack (RMS) battery cells have been determined thanks to dedicated multi-instrumented tests, while those of the AS4/8552 composite material have been extracted from the literature and validated by comparisons with tensile tests on plates without battery, considered as a reference case. Then, on the basis of the recommendations obtained from a virtual test campaign using FE simulations, a 16-ply laminated composite plate containing 6 solid battery cells was manufactured with a modified curing cycle that preserves the electrical properties of the batteries while ensuring the mechanical properties of the composite material. Various control methods, such as CT-scan and optical analysis, were used to demonstrate the promising quality of the manufactured composite coupon with embedded cells. Finally, a mechanical tensile test was carried out to experimentally determine the reduction in mechanical properties. The analysis of such a test with non-linear FE simulation has allowed a better understanding of the damage and failure process when solid battery cells are integrated into high performance laminated composite structures designed for the aeronautical industry.

Mechanical and dynamic thermal performance evaluation of rice husk blended cement plaster when used with different bricks

The construction industry is known for its significant environmental impact during the construction and operational phases. This study aims to explore the potential of rice husk, an abundant agricultural waste, as a partial replacement for sand in cement mortar. The research evaluates the thermo-mechanical properties, including compressive strength, water absorption, thermal conductivity, specific heat, and thermal diffusivity, of cement mortar by conducting a series of laboratory experiments. One of the critical novel aspects of this study is the evaluation of the dynamic thermal performance of the cement mortar when used with different bricks. The dynamic thermal performance was assessed using a MATLAB code based on the Charted Institute of Building Service Engineers (CIBSE) 2006 standard. By increasing the percentage of rice husk as a replacement for sand, the compressive strength of the cement mortar decreases, while the thermal conductivity decreases and the water absorption capacity increases. Notably, the results reveal that a 12 % reduction in thermal conductivity can be achieved by replacing just 7 % of the sand with rice husk. Furthermore, the study establishes a linear relationship between the dynamic thermal performance of the cement mortar and its volumetric heat capacity. These findings contribute to the development of eco-friendly solutions for energy-efficient buildings. The outcomes of this research can help engineers, architects, and policymakers in the decision-making processes regarding sustainable construction practices, promoting the use of rice husk as a viable alternative to sand.

Thermal and Mechanical Performance Evaluation of Nano-engineered Ultra-high Performance Cementitious Composite Using Microencapsulated Phase Change Materials

Thermal and Mechanical Performance Evaluation of Nano-engineered Ultra-high Performance Cementitious Composite Using Microencapsulated Phase Change Materials

A new secondary battery technology: Electrode structure and charge–discharge mechanism of all-solid-state zinc-graphite batteries

Zinc is abundant in the Earth's crust, which contributes to its relatively low price. Magnesium-based silicate, as a solid electrolyte material, is environmentally friendly due to its enhanced thermal stability compared to liquid electrolytes. Introducing a graphite film can reduce both the manufacturing process and the cost of zinc-ion solid-state batteries. This study fabricated an all solid-state zinc-graphite battery using an evaporated zinc-gallium (Zn-Ga) alloy film as the negative electrode, pressed magnesium-based silicate powder as the solid electrolyte, and graphite film as the positive electrode. The experimental results revealed the microstructure characteristics of the positive electrode, electrolyte, and negative electrode materials, while the charging-discharging mechanism and practical performance evaluation confirmed the high-efficiency energy storage capabilities of the all-solid-state zinc-graphite battery.

E-waste CRT panel glass reinforced magnesium composite processed through powder metallurgy: fabrication and mechanical performance evaluation

Cathode Ray Tube (CRT) panel glass with higher silica content has a potential to be used as reinforcement material in magnesium matrix composites. The present study aims to formulate a wear resistant magnesium hybrid composite by reinforcing silica rich E-waste CRT panel glass powder (0, 10 and 20 wt. %) and boron nitride (0, 2 and 4 wt. %) solid lubricant processed through powder metallurgy route. Composition of the CRT panel glass powder is identified through EDS and XRD analysis is performed for both base material and reinforcements. The developed green MMC shows increased hardness (∼53 %), porosity (∼7 %) and density (∼7 %) with respect to addition of CRT reinforcement. Porosity of hybrid composite increased vastly to 9.2 % when the CRT and BN content are increased to 20 % and 4 % respectively. A slight increment in (10 %) hardness is observed for 2 % addition of BN with Mg and Mg/CRT composite whereas hardness of the Mg and Mg/CRT MMC decreases with further addition of BN. The wear resistance of the composite enhanced with raise in CRT and BN content whereas the co efficient of friction decreases with increases in BN percentage. Corrosion behaviour of Mg is also analysed and found enhanced with reinforcement addition. It is identified from the results that the addition of CRT% up to 10 % yields significant results whereas further increase in CRT % to 20 provides only minor enhancements in properties. Further, it is suggested to restrict the addition of BN to 2 %.