Titanium Aluminum Research Articles

Poly (Vinylidene Fluoride-Hexafluoropropylene)-Lithium Titanium Aluminum Phosphate-Based Gel Polymer Electrolytes Synthesized by Immersion Precipitation for High-Performance Lithium Metal Batteries.

Gel polymer electrolytes (GPEs) have high safety and excellent electrochemical performance, so applying GPEs in lithium batteries has received much attention. However, their poor lithium ion transfer number, cycling stability, and low room temperature ionic conductivity seriously affect the utilization of gel polymer electrolytes. This paper successfully synthesized flexible poly (vinylidene fluoride-hexafluoropropylene)-lithium titanium aluminum phosphate (PVDF-HFP-LATP) gel polymer electrolytes using the immersion precipitation method. The resulting GPE has a porous honeycomb structure, which ensures that the GPE has sufficient space to store the liquid electrolyte. The GPE has a high ionic conductivity of 1.03 ×10-3 S cm-1 at room temperature (25 °C). The GPE was applied to LiFePO4/GPE/Li batteries with good rate performance at room temperature. The discharge specific capacity of 1C was as high as 121.5 mAh/g, and the capacity retention rate was 94.0% after 300 cycles. These results indicate that PVDF-HFP-LATP-based GPEs have the advantage of simplifying the production process and can improve the utility of gel polymer lithium metal batteries.

Material Selection Using Hybrid Grey Relation Analysis Approach Based on Weighted Entropy for Ranking: The Case of Helicopter Rotor Blade

Engineering design relies highly on the selection of suitable materials. Because there are many engineering materials, selecting a suitable material for a product requires a systematic selection approach. This paper provides a hybrid strategy for choosing the best material for an engineering design to give the best performance at the lowest cost based on Ashby's performance indices. Then, it ranks the result by the grey relational approach integrated with the Weighted Entropy Method to choose the optimum material for the main rotor blade of a helicopter. Different materials used for manufacturing rotor blades, such as Aluminium alloys, titanium alloys, steel, composites, and wood, have been discussed. The performance indices chosen are stiffness, strength, and fracture toughness. The performance indices proved that the composite material has excellent structural strength, stiffness, and toughness. The result shows that CFRP is the best material for manufacturing helicopter rotors, while wood and steel were the best and cheapest when the design had to be economical.

Double side friction stir Z shape butt lap welding of dissimilar titanium aluminum alloys

Achieving excellent mechanical performance of medium-thick Ti/Al dissimilar joints is important in many industrial applications. However, due to the inherent heat generation mode associated with conventional friction stir welding (FSW), it is impossible to achieve sound medium-thick Ti/Al dissimilar joints. Although double side friction stir welding (DS-FSW) has been reported to solve the problems of conventional FSW. The inherent problems of forming hook structure and interface cracking in the center of the DS-FSW joints significantly weaken the joint performance. Therefore, an innovative double-side friction stir Z shape butt-lap welding (DS-FSZW) process was proposed to eliminate the inherent problems of conventional DS-FSW. The research objective of this work was to reveal the physical mechanisms of the novel DS-FSZW by the combination of numerical simulation and experimental characterization for optimizing the welding parameters. The influence of tool shoulder diameter on the heat generation, heat transfer, plastic material flow, microstructure evolution and mechanical properties of medium-thick dissimilar Ti/Al DS-FSZW joint has been systematically studied. The results indicate that the innovative DS-FSZW process lowers the axial force compared to the conventional DS-FSW, and the centerlines of the first and the second sides welds are staggered. Those are beneficial to inhibiting the cracking of the first-side weld at the interface. In addition, the DS-FSZW method eliminates the hook structures and cracks at the center of the conventional DS-FSW joint and also adds a lap joining interface, which significantly enhances the tensile strength of the joint from 150.7 MPa to 262.5 MPa, which is increased by 74%. Optimization of the shoulder diameter of DS-FSZW from 18 mm to 12 mm reduces the welding heat input and significantly thins the thickness of the IMCs layers at the Ti/Al interface. This helps to suppress the cracking at the Ti/Al lap interface and refine the grains. As a result, thus the tensile strength of the DS-FSZW joint increases from 262.5 MPa to 312.5 MPa, which is increased by 19%. The medium-thick Ti/Al dissimilar DS-FSZW joint at the tool shoulder diameter of 12 mm fracture at the SZ. It proves that the novel DS-FSZW is a suitable welding method for joining medium-thick dissimilar Ti to Al alloys.

Exergy-energy, sustainability, and emissions assessment of Guizotiaabyssinica (L.) fuel blends with metallic nano additives

This study extensively examined the impact of aluminium oxide (Al2O3) and titanium dioxide (TiO2) nanoparticles addition in the biodiesel fuel derived from Guizotiaabyssinica (L.) oil. The assessment of fuel blends, which were created by combining nanoparticles and biodiesel was conducted using energy, exergy, and sustainability indices. The highest recorded power output of 2.81 kW was observed for the GAB20A engine operating at 1800 rpm. The experimental results revealed that the GAB20A exhibited the lowest fuel consumption, with a recorded value of 203 g/kWh, when operated at 1600 rpm among all the tested blend fuels. The blend GAB20A exhibited the highest level of energy efficiency at 1600 rpm of 29.5%, as determined by the study. Simultaneously, it was observed that GAB20 exhibited the lowest energy efficiency at 1200 rpm among all the blend fuels at 25%. The emission levels of nitrogen oxides (NOx) and carbon monoxide (CO) were observed to be quite low, although a little rise in carbon dioxide (CO2) was detected. For validation of results the artificial neural network (ANN) was used and an average of 1.703% difference in energy efficiency, 2.246% decrease in exergy efficiency, and 1.416% difference in sustainability index was found.

An Experimental Study on the Performance Enhancement of a Heat Pump System using Nanofluids

Heat pumps are frequently used for heating, cooling, and air conditioning. It is well known that nanoparticles can improve the coefficients of conduction and convection, increasing heat transfer along with other properties. The considered heat pump was loaded with R-134a. Titanium dioxide (TiO2) and aluminium oxide (Al2O3) were blended with clean water to create a nanoscale solution used to cool the heat pump condensers. A total of three TiO2 and Al2O3 proportions (0.1%, 0.2%, and 0.3%) were used. The study's findings showed that utilizing 0.3% Al2O3 instead of conventional clean water to cool the heat pump condenser boosted the coefficient of performance by 18% while reducing energy consumption by 26%.

Effect of temperature on the healing capacity and mechanical properties of Ti2AlC MAX phase ceramics

AbstractIn this study, the self‐healing capacity of Titanium Aluminum Carbide (Ti2AlC, MAX phase) was investigated. Bulk coin samples were fabricated to evaluate the self‐healing capacity at different temperatures (1000, 1200, and 1400°C). The extensive self‐healing capacity of Ti2AlC was confirmed on larger quasiplastic damage (diameter ≥1 mm) and radial cracks by covering and filling of oxides such as titanium oxide, aluminum oxide, and aluminum titanate oxide. Although the mechanical properties of Ti2AlC after healing are similar or improved relative to the Ti2AlC before healing at the microscale, some properties of Ti2AlC after introducing larger damage and healing at 1400°C showed reduced values due to excessive oxide formation on the surface. For example, the strength of Ti2AlC healed at 1400°C exhibited 151.4 MPa, which is relative to the original strength of 298.3 MPa. Alternatively, the mechanical properties such as strength, hardness, toughness, and relative modulus of elasticity of Ti2AlC healed at 1000 or 1200°C and were restored to their original strength after healing. These findings suggest that Ti2AlC can be used as a healing agent for high‐temperature applications, such as environmental barrier coating for gas turbine hot‐gas components.

Nonsimilar mixed convection analysis of ternary hybrid nanofluid flow near stagnation point over vertical Riga plate

PurposeThis work aims to concentrate on the mixed convection of the stagnation point flow of ternary hybrid nanofluids towards vertical Riga plate. Aluminum trioxide (Al2O3), silicon dioxide (SiO2) and titanium dioxide (TiO2) are regarded as nanoparticles, with water serving as the base fluid. The mathematical model incorporates momentum boundary layer and energy equations. The Grinberg term for the viscous dissipation and the wall parallel Lorentz force coming from the Riga plate are taken into consideration in the context of the energy equation.Design/methodology/approachThrough the use of appropriate nonsimilar transformations, the governing system is transformed into nonlinear nondimensional partial differential equations (PDEs). The numerical method bvp4c (built-in package for MATLAB) is used in this study to simulate governing equations using the local non-similarity (LNS) approach up to the second truncation level.FindingsNumerous graphs and numerical tables expound on the physical properties of the nanofluid temperature and velocity profiles. The local Nusselt correlations and the drag coefficient for pertinent parameters have been computed in tabular form. Additionally, the temperature profile drops while the velocity profile increases when the mixed convection parameter is included to oppose the flow.Originality/valueThe fundamental goal of this work is to comprehend how ternary nanofluids move towards a vertical Riga plate in a mixed convective domain with stagnation point flow.

Machinability of Inconel 718 using unitary and hybrid nanofluids under minimum quantity lubrication

ABSTRACT In the current study, unitary and hybrid nanofluids are used with minimal lubrication to examine Inconel 718’s machinability. Nanofluids are obtained by dispersing unitary and mixed amounts of aluminium oxide, multi-walled carbon nanotubes, and graphene nanoparticles into palm oil. Initially, turning experiments were performed with pure palm oil and different unitary and hybrid nanofluids using differently coated carbide tools to obtain the best combination of the type of nanofluid(s) and coated tool for the lowest tool wear. Further, the cutting forces, surface roughness, chip thickness ratio, chip morphology, and shear angle were obtained, varying with the cutting parameters for the best combination of nanofluid(s) and the tool. The analysis of worn-out tools has been performed through images captured using optical and scanning electron microscopes. The study indicates that aluminium titanium nitride-coated tools outperform titanium aluminium nitride-coated tools with hybrid aluminium oxide and multi-walled carbon nanotube-based nanofluid, followed by a unitary aluminium oxide-based nanofluid. It could be attributed to the higher thermal conductivity and surface tension of aluminium oxide nanoparticles and the better lubricating and cooling capabilities of multi-walled carbon nanotubes. Comparatively lower performance was observed with graphene-based nanofluid due to severe agglomeration that adversely affected the homogeneity of the fluid.

Converting a Commercial Separator into a Thin‐film Multi‐Layer Hybrid Solid Electrolyte for Li Metal Batteries

AbstractTo address the manifold challenges solid electrolytes (SE) do face in NMC‖Lithium metal batteries, we demonstrate that these can be overcome by converting a commercial Celgard 2500 separator into a jack of all trades hybrid solid electrolyte (HSE). This approach follows a multi‐layer electrolyte strategy, to better cope with the very different chemistries of the cathode, the bulk electrolyte material, and the Li metal anode. A cathode‐facing electrolyte layer based on lithium aluminum titanium phosphate (LATP) provides a high voltage stability of ≥4.5 V. High mechanical strength of the overall thin film electrolyte (≤50 μm) is achieved with a middle layer based on Celgard 2500. The layer on the anode side, based on polyethylene oxide (PEO), allows stable cycling of the lithium metal. High Coulombic efficiencies in NMC622‖Li metal cells (99.9 %) and LFP‖Li metal cells (99.9 %) enable long term cycling with high‐capacity retention of 46 % and 52 % after 1,000 cycles, respectively.

Temperature Effects on Critical Energy Release Rate for Aluminum and Titanium Alloys

This work investigates temperature’s effect on the critical energy release rate using damage mechanics material models and the element deletion method. The energy release rate describes the decrease in total potential energy per increase in crack surface area. The critical energy release rate is widely used as the failure criterion for various elastic and plastic materials. In real-life scenarios, fractures may occur at different temperatures. The temperature dependency of the critical energy release rate for aluminum 2024-T351 and titanium Ti-6Al-4V is studied in this work. We utilized test-data-based advanced material models of these two alloys, considering the strain rate, temperature, and state of stress for plasticity and failure. These material models are used to simulate a three-dimensional fracture specimen to find the critical energy release rate at different temperatures. A new method to calculate the critical energy release rate with the element deletion method is introduced and verified with the virtual crack opening method. This method enables the calculation of the energy release rate in a classical damage mechanics simulation for dynamic cack propagation. The simulation result indicates that the critical energy release rate increases with rising temperatures for these alloys.

Effect of calcium phosphate/bovine serum albumin coated Al2O3-Ti biocomposites on osteoblast response.

The biological performance of aluminum oxide-titanium (Al2O3-Ti) composites requires special attention to achieve improved osteoblastic differentiation, and subsequent osseointegration/strong anchorage with the surrounding bone. Therefore, the aim of this study was to improve them by providing calcium phosphate (Ca-P)/bovine serum albumin (BSA) coating on their surfaces. Ca-P/BSA coatings were prepared on the surfaces of 75vol.%Ti composites (75Ti-BSA) and pure Ti (100Ti-BSA as a control). The surface characteristics, phase analysis, micro-hardness, BSA release profile and biological responses including cytotoxicity, cell viability, differentiation, mineralization, and cell adhesion were evaluated. The results showed that lower cytotoxicity% and higher mitochondrial activity or viability % were associated with the samples with Ca-P/BSA coatings (particularly 75Ti-BSA having 21.3% cytotoxicity, 111.4% and 288.6% viability at day 1 and 7, respectively). Furthermore, the Ca-P/BSA coating could highly enhance the differentiation of pre-osteoblast cells into osteoblasts in 75Ti-BSA group (ALP concentration of 4.8 ng/ml). However, its influence on cell differentiation in 100Ti-BSA group was negligible. Similar results were also obtained from mineralization assay. The results on cell adhesion revealed that the Ca-P/BSA coated samples differently interacted with MC3T3-E1 cells; enlarged flat cells on 75Ti-BSA vs more spindle-shaped cells on 100Ti-BSA. Ca-P/BSA coated Al2O3-Ti provided promising biological performance, superior to that of uncoated composites. Therefore, they have the potential to improve implant osseointegration.

Lead-bismuth eutectic corrosion resistance of TiAlN coating after N5+ ion irradiation

In this study, a Ti0.33Al0.67N coating with Cr as the transition layer was prepared by cathodic arc-ion plating. After irradiation with N5+ ions, the coating was exposed to lead-bismuth eutectic (LBE) at 450 °C for 3000 h. The effect of irradiation on the corrosion resistance of the coatings was also investigated. No evidence of an LBE corrosion attack was observed in either the irradiated or unirradiated coatings. Transmission electron microscopy images revealed that the nanoscale oxide layer on the surface of the titanium aluminum nitride coating was the main barrier to LBE corrosion. The unirradiated coating had a single oxide layer, whereas the irradiated coating had a double oxide layer. Irradiation also affects the coating adhesion by inducing stress. However, after the corrosion test, the adhesion of all coating samples unexpectedly increased and were almost at the same level. The coating exhibited excellent properties after irradiation and LBE corrosion; therefore, the coating can be applied in future nuclear reactors.

Finite element analysis of cross fluid model over a vertical disk suspended to a tetra hybrid nanoparticles mixture

Nanoparticles have numerous applications and are used frequently in different cooling, heating, treatment of cancer cells and manufacturing processes. The current investigation covers the utilization of tetra hybrid nanofluid (aluminum oxide, iron dioxide, titanium dioxide and copper) for Crossflow model over a vertical disk by considering the shape effects (bricks, cylindrical and platelet) of nanoparticles, electro-magneto-hydrodynamic effect and quadratic thermal radiation. In the current inspection model is first derived given PD-equations and then altered into a system of OD-equations by including similarity variables. The converted ordinary differential equations are solved by using the finite element procedure and the impact of the solution against numerous involved parameters is displayed through tables and graphs. It is observed that tetra-hybrid nanoparticles are recommended better in industrial applications where the highest production of thermal energy. Moreover, an enhancement of thermal production can be achieved utilizing different values of the magnetic parameter, time relaxation number, variable thermal radiation number and magnetic induction number but the opposite trend has been noticed with the effects of radiation number.

Evaluation of the titanium, aluminum and silicon oxides effect on the copolyamides synthesis and their properties

The effect of inorganic additives on the ε-caprolactam with ω-dodecalactam anionic (co)polymerization process and on the properties of synthesized samples is investigated. Aluminum oxide, titanium dioxide and silicon dioxide were used as inorganic additives. It is shown that the introduction of additives at a 1 mol.% concentration at the stage of copolycaproamide synthesis contributes to a decrease in the ε-caprolactam with ω-dodecalactam anionic (co)polymerization rate. The influence of the selected additives on the physico-mechanical, thermal and operational properties complex has also been studied. It was found that the use of inorganic additives at a 1 mol.% concentration at the synthesis stage contributes to an increase in destruction temperatures compared to unmodified samples. It was found that the introduction of aluminum oxide, titanium dioxide and silicon dioxide leads to an increase in physical and mechanical parameters and Shore hardness, a decrease in water absorption and oil and gasoline resistance.

Investigation into the Influence of the Process Parameters on the Stability of a Poly(Vinyl)-Alcohol-Based Coating System.

Most tablets put on the market are coated with polymers soluble in water. The Opadry II 85 series from Colorcon Inc., is a family of PVA-based products marketed since the 1990s. Despite numerous publications on the properties of PVA, to date, limited work has been undertaken to determine the physico-chemical parameters (i.e., UV light, high temperature, and relative humidity) that could affect the performance of PVA-based coatings. To this end, we performed artificial ageing processes on samples made of Opadry Orange II or of some selected components of this coating and analysed them by means of a multidisciplinary approach, using, for example, FTIR, NMR, rheology, and DMTA measurements. In this way, we analysed the influence of the critical components of the Opadry Orange II formula, such as titanium dioxide and aluminium hydroxide, on the coating characteristics under ageing conditions.

The Temperature Field Prediction and Estimation of Ti-Al Alloy Twin-Wire Plasma Arc Additive Manufacturing Using a One-Dimensional Convolution Neural Network

Plasma arc deposition as an additive manufacturing technology has unique advantages for producing parts with complex shapes through layer-by-layer deposition. It is critical to predict and control the temperature field during the production process due to the temperature distribution and gradients determining the properties and performance of the part. Numerical simulation approaches, such as the finite element method, which provides a large amount of data for machine learning modeling, thus reducing the overhead of experimental measurements, are widely used in machine learning. In this paper, we propose a neural network combined finite element method and process prediction workflow. A one-dimensional convolutional neural network model for predicting 2D temperature distribution is developed by training the collected data on the planar temperature field of titanium–aluminum twin-wire plasma arc additive manufacturing and the finite element method. The results show that the predicted temperature mean square error is only 0.5, with less than a 20 °C error in peak temperature and a relative error below 1%. The proposed transfer learning method achieves the same training loss and is 500 iterations faster than basic training, which improves the training speed by 25%. The current study confirms the accurate performance of the ML model and the effectiveness of the optimization method.

Fabrication, sintering behavior and mechanical properties of calcium oxide doped yttrium oxide refractory via aqueous gel casting method

Yttrium oxide is an ideal choice for titanium aluminum alloy melting and casting, its wider use is hindered by sintering challenges and low thermal shock resistance. To address this, we propose a gel casting method for calcium oxide-doped yttrium oxide production. We pretreated yttrium oxide with phosphoric acid to prevented hydrolysis and adjusted the isoelectric point of yttrium oxide to match calcium carbonate's. Anions from calcium carbonate increased slurry solid content (up to 58 vol%) while maintaining low viscosity (57.78 mPa·s at 40 s−1 shear rate). After sintering at 1650 °C for 2 h, the material showed a flexural strength of 78 MPa, with a 90% retention rate after thermal shock test. The introduction of calcium oxide induced lattice distortion, improving mechanical properties by aiding sintering and grain boundary diffusion. XPS and STEM analysis confirmed random replacement of Y3+ by Ca2+ at the C2 position with 1 wt% doping.

ESTIMATION OF FATIGUE CURVES USING ORTHOGONAL POLYNOMIALS

The article proposes a methodology for processing fatigue tests carried out to assess the fatigue curve of materials and structural elements, the most important design characteristic of the endurance, service life and reliability of aircraft products, transport engineering and other structures operating under conditions of both regular and irregular loading. The task of estimating the parameters of the fatigue curve is often complicated by the limited scope of fatigue tests, significant scattering of cyclic durability, uneven duplication of experiments at a given level of alternating stress amplitudes, the presence of censoring, especially at low levels, and other factors. which necessitates the use of the weighted least squares method. These circumstances lead to the violation of the conditions for using standard methods of regression analysis and the least squares method. This is especially true for the confidence assessment of the fatigue curve, the accuracy of which significantly depends on these factors. For this purpose, the article proposes to apply the procedure of orthogonalization of factor characteristics to estimate the parameters of the fatigue curve, which reduces the errors arising from standard approaches and makes it possible to obtain accurate confidence intervals for durability. A special feature of the technique is the use of orthogonal polynomials in statistical procedures, which makes it possible to modify the covariance matrix of estimates by converting it to a diagonal form, regardless of the spread of the weight parameters of the original data. These transformations make it possible to perform statistical procedures for point and confidence estimation when processing the results of fatigue tests. To test the methodology, a statistical analysis of a large volume (about 200 samples) of fatigue tests of samples with varying degrees of stress concentration from titanium alloy VT3-1 and aluminum alloy V-95 was performed, algorithms and computer programs were developed in the public domain.

Conductive filament distribution in nano-scale electrochemical metallization cells.

We report a combined experimental and theoretical study of the spatial distributions and sizes of conductive filaments in nano-scale electrochemical metallization (ECM) cells. Each cell comprises a silver nanocube as active electrode, a titanium dioxide (TiO2) or aluminum oxide (Al2O3) layer as dielectric, and a highly-doped silicon substrate as passive counter electrode. Following electroforming of the ECM cell and subsequent mechanical delamination of the silver nanocubes, current maps at previous particle locations reveal an intriguing metal distribution in the TiO2, with preferential accumulation close to the original locations of the nanocube edges. We assign this behavior to electric field enhancements close to the cube edge positions. In contrast, filaments in Al2O3 layers show a comparatively homogenous distribution, which may be assigned to its lower dielectric permittivity. By increasing the oxide thickness, the total area of conductive spots in the current maps increases monotonically for both materials. Kinetic Monte-Carlo simulations of ion migration dynamics in TiO2 confirm the experimental observations, describing both the preferred locations and oxide thickness-dependent metal loadings associated with filament formation. Overall, our findings are highly valuable for the design of future electrochemical metallization cells, especially in the sub-100 nm regime, where optimal filament control is of major importance for achieving lowest device-to-device variability.

Pre and post-operative serum levels of titanium cobalt and aluminium after implant placement.

The preoperative serum levels and postoperative serum levels of titanium, cobalt and aluminium from dental implants in order to assess the release of these ions and to assess any risk of toxicity from these ions after dental implant placement is of interest to dentists. It was observed that there was very slight increase in serum concentration of titanium, cobalt and aluminium after 12 months of placement of implants as compared to before placement of implants. However the increase was non-significant statistically. Our study concluded that the use of dental implants does not pose any risk of toxicity of metal ions like titanium, aluminium and cobalt because of very slight non-significant increase in serum levels of these ions 12 months after implant placement.