Hard Materials Research Articles

Assessing melt pool temperature independence from hardness via photodiode-based plank thermometry (PDPT)

Directed Energy Deposition (DED) has emerged as a promising metal additive manufacturing technique due to its ability to create components comparable or superior to traditional fabrication. Although industrial adoption of this technology is underway, there exists a considerable need to improve the predictability of the components it manufactures to promote wider adoption of this technology. Currently, melt pool temperature is the primary metric for build monitoring and control. However, stronger correlations must be established between the process parameters, including melt pool temperature, and resulting material outcomes to determine if melt pool control is a sufficient metric to control part quality. The goal of this research is to establish correlations between laser power (W), scanning speed (mm/s), powder flow rate (g/min), average melt pool temperature (C), and hardness. The average melt pool temperature was measured through Photodiode-based Planck thermometry (PDPT) with dual on-axis photodiodes. To obtain the correlation between these factors, 54 samples of Inconel 718 were printed, cross-sectioned, and tested using a Vickers diamond indenter. The resulting correlations exhibited extremely low R2 values and validated the findings of previous studies in that process parameters are exceedingly poor predictors of component properties. Average melt pool temperature lacked a significant correlation with hardness, instead process scanning speed demonstrated a more significant impact on the final material hardness. Since hardness is largely dictated by average grain size which in turn is controlled primarily by solidification rate, solidification rate should be the focus of future work to control material properties. The results of this study indicate that melt pool thermal control is not a sufficient metric to control part quality, and a solution is needed that can oversee the build process in such a way that solidification rate can be monitored and controlled in addition or instead of melt pool temperature. Future work must be done to apply the PDPT methodology to real time calibrated indirect measurement of melt pool solidification rates to improve prediction and control of final part mechanical properties.

Optimization of Material Removal Rate and Wear Rate in EDM Machining of Inconel 625 Using a Novel Nano Al-Ni Composite Electrode: A Response Surface Methodology Approach

The electric discharge machine is a novel machining technique. When the tool and the work item do not communicate. Components composed of difficult-to-machine hard materials. In the current experimental inquiry, the process factors that influence the machining concert process and its effectiveness are explored. The response table for each set of machining limitations is used in conjunction with the response surface methodology in the research to determine the appropriate levels of machining factors. The work's machining input parameters are optimized for maximum material removal rate (MRR) and reduce the electrode wear rate (EWR) when electro-discharge machining Inconel 625 using the tool Nano Al-Ni composite electrode. Another analysis of variance is to identify the factors causing the different answers mentioned above. EDAX was also used to investigate the material composition of the workpiece. Machined workpiece surfaces were evaluated using scanning electron microscopy to assess surface accuracy and microstructural characteristics (SEM). The following conclusions may be drawn from this work. The MRR parameter that is most affected is pulse off time. As pulse-off time lengthens, MRR increases. According to the response graph, the greatest MRR value that can be attained under the ideal parameters of Ip = 8A, T-ON = 50μs, and T-OFF= 100μs is 0.0115 g/min. The magnitudes of MRR range from 0.0091 to 0.044 g/min. Impact of T ON and T OFF: Higher EWR is 0.0022 g/min is seen in runs with T ON = 70 μs and T OFF = 100 μs.

COMPARATIVE EVALUATION OF HARDNESS AND SURFACE ROUGHNESS AFTER DIFFERENT COOLING PROCEDURES OF HEAT CURE DENTURE BASE MATERIALS

Aim: To evaluate the influence of different cooling procedures on mechanical properties of DPI & LUCITONE heat cure poly methyl methacrylate denturebase materials before andafter 1year of brushing simulation. Materials And Methods: A total of 100 specimens were prepared using two heat cure denture base materials i.e, DPI and LUCITONE. The specimens in each group were subdivided into five groups (n=10 ) based on the cooling procedure followed: A: Flask remains in water bath till room temperature B: Remove flask from water bath, bench cool for 30min and then cool under running water for 15min C: Remove flask from water bath, bench cool for 10min and then cool under running water for 15min D: Remove flask from water bath and bench cool till room temperature E: Remove the flask from water bath and cool under running water for 15 minutes.After finishing and polishing, samples were placed in a brushing machine to simulate one year of mechanical cleansing. The specimens were tested for surface roughness with profilometer and hardness with Vickers hardness tester before and after brushing. Results were statistically analysed by two and one- way Analysis of variance (ANOVA) plus Tukey post hoc tests. Results: Specimens with type C(Remove flask from water bath, bench cool for 10min and then cool under running water for 15min)cooling procedures have high hardness values, among whichLucitone showed better properties. Surface roughness did not show significant changes among different groups. Brushing did not significantly affect surface roughness and hardness of denture base materials. Conclusion: Two of the treatments tested, Treatment C: bench-cooling for 10 min and cooling under running water for 15min and Treatment A: cooling in water-bath till room temperature provided the highest hardness values.

Revisiting Rare Earth Permanent Magnetic Alloys of Nd-Fe-C

Nd-Fe-C alloys have been reported as hard magnetic materials with a potential higher coercivity than Nd-Fe-B alloys. However, it has been seldom studied since its intrinsic properties were investigated in the last century. Here, we revisited the structure, phase precipitation and magnetic properties of rapidly quenched ternary Nd-Fe-C alloys for further understanding their composition-microstructure-property relationships. The Nd10+xFe84−xC6 (x = −2, 0, 2, 3, 4, 5) alloys with various compositions were prepared by melt spinning. The results show that the hard magnetic Nd2Fe14C phase can be hardly formed in the as-spun alloys. Instead, the alloys are composed of soft magnetic α-Fe phase and planar anisotropic Nd2Fe17Cx phase. After annealing above 650 °C, the Nd2Fe14C phase is precipitated by the peritectoid reaction. All optimally annealed alloys contain Nd2Fe14C and Nd2Fe17Cx phases, while the presence and content of α-Fe phase are determined by the alloy composition. The crystallization degree of the as-spun alloys has an effect on their magnetic properties after annealing. After the annealing treatment, partly crystallized as-spun alloys exhibit better magnetic properties than the amorphous alloys. The intrinsic coercivity Hcj = 847 kA/m, remanence Jr = 0.69 T, and maximum energy product (BH)max = 64.3 kJ/m3 were obtained in the Nd14Fe80C6 alloy annealed at 725 °C. The formation of the Nd2Fe14C and Nd2Fe17Cx phases with the Nd2O3 phase precipitated at the triangular grain boundaries is responsible for its relatively good properties. Although the magnetic properties of Nd-Fe-C alloys obtained in this work are inferior to those of Nd-Fe-B, the present results help us to further understand the magnetic behavior of Nd-Fe-C alloys.

EFFECTS OF HEAT TREATMENT ON THE IMPROVED WEAR RESISTANCE OF SHOT BLAST MACHINE BLADE MATERIAL

The blade is a component of the shot blast machine that functions as a thrower of small steel balls (steel shot). During its use, the blade undergoes impacts and friction with the steel shot, causing wear and a shortened lifespan. The material typically used for blades is white cast iron. Hence, the blade must possess good hardness and wear resistance. This study analyzed the causes of blade failure and proposed solutions in the form of hardening and tempering treatments. The tests conducted in this research included composition analysis, metallographic examination, hardness testing, and wear resistance testing. Based on the composition and hardness tests, the failure was attributed to material composition and hardness not meeting the ASTM A532 standards. The solution to this failure involves heat treatment to achieve hardness that complies with ASTM A532 standards, specifically hardening at 900°C for 40 minutes, followed by cooling with oil as the quenching medium. Then, the tempering process was carried out at 200°C, 250°C, and 300°C with holding times of 80 and 120 minutes. Post-heat treatment, the optimal hardness value, and the lowest wear rate were obtained at a tempering temperature of 300°C with a holding time of 120 minutes. The hardness value of the blade material under these conditions reached 63.8 HRC, and the wear rate was 1,21E-04 mm3.kg-1.m-1. A low wear rate indicates that the material has high wear resistance.

Enhancing Surface Quality and Tool Longevity in EDM of D2 Steel Using Copper Composite Tools

Hard material machining and die manufacture are the main applications for electrical discharge machining (EDM). For EDM, conventional electrode materials include graphite, steel, brass, pure copper, and alloys based on copper. Unfortunately, excessive tool wear is a common problem with these materials, which raises the cost of machining. In this investigation, hardened D2 steel was machined using a composite tool made of 90% copper and 10% silicon carbide. The powder metallurgy method was used to create the composite tool. Surface roughness (SR) and electrode wear rate (EWR) were compared to a number of process variables. For experimentation, a response surface methodology based on CCD design in design of experts software was used. SR and electrode wear rate models were created using the CCD approach. Utilizing analysis of variance, the most important factors and their effects on EWR and SR were determined. The lowest tool wear rate of 0.39 gm/min is achieved with a current of 5 Amps, a pulse duration of 100 µs, and a pulse interval of 10 µs with an R2 of 0.9957, which accounts for 99.57% of the variability, the tool wear rate model fits the data very well and obtained lowest surface roughness of 2.8 µm.

Does static friction information predict the onset of sliding for soft material?

Friction behavior between soft and hard materials has long been a question of great interest in the fields of artificial joints, human skin contact, robotic grippers, and others. In this study, we presented a combination of theoretical and experimental analyses to investigate the friction behavior of soft materials. Using some geometric and stick–slip features in the early stage of static friction, the friction property of the interface between a soft material and a hard material is determined. Moreover, the onset of slip, the threshold force at which a friction interface begins to slide, is also predicted by a theoretical model. The predictive ability of this model may provide insights for improving interaction property recognition, as well as for developing fine tactile feedback and dexterous operation of robotic grasping.

Design of cross-linked hard carbon with high initial coulombic efficiency for sodium-ion batteries anode

Cross-linked hard carbon materials (SFCzGLC1) were prepared from Shenfu bituminous coal (SFC) and glucose (GLC) via a one-step carbonization method. The relationship between the microstructure and Na+ storage behavior was explored. The initial coulombic efficiency (ICE) was related to surface defects. Owing to abundant porous structure and low defects, SFC3GLC1 delivered the highest reversible capacity of 413.1 mAh/g at 0.02 A/g with ICE ∼84 % and excellent cycling stability (89.4 % capacity retention over 200 cycles). This work provides a facile route to develop high-performance, low-cost carbon-based anodes for next-generation sodium-ion batteries (SIBs).

Multi-objective optimization of micro crystalline cellulose and montmorillonite filled poly lactic acid bio–composite and its characterizations

In this research study, the synthesis of poly lactic acid (PLA) based bio composite material factors contributions were investigated through the Taguchi-based grey relational analysis (GRA) technique. Effects of micro crystalline cellulose (MCC) and montmorillonite (MTT) nano clay filler, sorbitol (S) plasticizer, and temperature (T) operating factor on the PLA matrix through melt-mixing preparation method. The tensile strength (TS), Young modulus (YM), flexural strength (FS), flexural modulus (FM), hardness, impact strength (IS), water absorption (WA), and density properties of bio composite material were investigated for each experimental setup (orthogonal array, L16). Additionally, neat PLA and optimal sample structural, thermal, and morphological properties were examined through Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (X-RD), thermal gravimetry analysis/differential thermal gravimetry (TGA/DTG), and DSC and SEM analyses. The obtained result for optimal mechanical and physical properties of MCC/MTT/S/PLA bio composite was MCC at level 3 (6%), MTT at level 4 (9%), S at level 2 (10%), and T at level 4 (175 °C). Analysis of variance (ANOVA) shows that MTT has the greatest significant effect on mechanical and physical properties of MCC/MTT/S/PLA bio composite followed by MCC, T, and S. The confirmation test indicates that the improvement of weighted grey relational grade (GRG) from 0.7896 to 0.846 and the FTIR, XRD, thermal gravimetry/differential scanning calorimetry (TG/DSC), and scanning electron microscopy (SEM) results indicates that the good interaction between PLA and fillers, improvement of thermal and morphological properties of optimal (6MCC/9MTT/10S/175 °C) bio composite samples. Therefore, the multi-response characteristics of MCC/MTT/S/PLA bio composite can be highly improved by this technique.

Analysis of Friction and Wear Properties of Friction Ring Materials for Friction Rings under Mixed Lubrication

Aiming at the problem of mechanical seal failure due to serious wear and tear in operation, the numerical model of the thermal–solid coupling wear of the seal ring is established by taking the friction sub-material as the research object, and the hardness, wear coefficient, and friction coefficient of different soft-ring materials are obtained by a test to verify the accuracy of the numerical model of wear. Additionally, the temperature field and deformation field of the seal ring of different materials are calculated, and the effects of the material parameters, such as elasticity modulus and thermal conductivity, on the temperature, relative deformation, and axial deformation trend are reported. The wear relation of the mechanical seal was optimized, and the correction coefficients of several materials were calculated. The results show the following: the main wear of the seal ring is due to adhesive wear leading to particle shedding and extrusion, adhesive wear causes material transfer, which alters the composition of the worn surface.in turn leading to cratering, which also causes the wear of the seal ring; the friction performance is better when the soft-ring material is graphite (C); the temperature, as well as the deformation, is smaller when the soft-ring material is silicon carbide (SIC); the correction coefficients for the life of SIC are calculated to be 0.23, for C, to be 0.14, and for stainless steel (Ss), to be 0.31, and the corrected equations can more accurately predict the corresponding material. The corrected equation can more accurately predict the service life of the corresponding material.

Flexure Performance of Textile-Reinforced Cementitious Composites with Novel Inclined Reinforcements.

Textile-reinforced cementitious composites have great potential to offer novel design opportunities for thin-section structures thanks to their superior material capabilities. In this work, new cementitious composites with novel reinforcement configurations are developed, which have superior mechanical properties. The cementitious composites contain inclined through-the-thickness reinforcements, and their enhanced performance on thin-section material hardening under flexural loading is demonstrated. Furthermore, a new practical FE modeling approach is proposed that involves the combined use of multiple cohesive regions and 1D reinforcement elements that pass through these regions with a bilinear material law. This approach provides a new computationally efficient modelling framework whereby reinforcement pull-out during hardening is readily captured without resorting to computationally demanding interface laws between the reinforcement and the cementititous matrix. The model can model enhanced hardening of new configurations and provides comparable results with the experimental findings. The model can be used in the modelling and design of novel cementitious composites with engineered reinforcement configurations. Overall, this study aims to open up new avenues for the smart material design of cementitious composites with novel structural reinforcements.

Dependence of wear of friction pairs of the mechanism for loading solid household waste into a garbage truck on the characteristics of antifriction materials

The article is dedicated to the establishment a regression dependence of wear of friction units of the mechanism of loading a garbage truck on the properties of antifriction materials. By using a first-order planning of experiment with first-order interaction effects using the Box-Wilson method, an appropriate regularity of wear of friction units of the garbage truck loading mechanism on the properties of antifriction materials has been determined. It is established that, according to the Student's criterion, among the studied factors of influence, the wear of friction units of the garbage truck loading mechanism is most influenced by the pressure in the friction zone, and the least – by the Brinell hardness of the antifriction material. The response surfaces of the objective function – wear of friction units of the garbage truck loading mechanism and their two-dimensional cross-sections in the planes of the influence parameters are shown, which allow to clearly illustrate the specified dependence of this objective function on individual influence parameters. It has been established that an increase in the pressure in the friction zone and sliding speed by 60% leads to an increase in the wear of friction units of the garbage truck loading mechanism during reverse motion by 6.3...34%, depending on the properties of antifriction materials. The expediency of conducting further research to determine ways to further improve the wear resistance of friction units of the mechanism for loading solid household waste into a garbage truck has been shown.

The induced formation and regulation of closed-pore structure for biomass hard carbon as anode in sodium-ion batteries

Biomass hard carbon is regarded as an advanced anode materials for sodium ion batteries (SIBs) since it possesses balanced performance including satisfactory specific capacity, suitable operating voltage window and low cost. Although numerous instances of utilizing biomass-derived hard carbon in SIBs have been observed, the unregulated pore structure of these hard carbon materials significantly constrains the electrochemical performance of SIBs, leading to diminished initial Columbic efficiency (ICE) and plateau capacity. Herein, taking a biomass hard carbon derived from waste camellia seed shells (CSSHCs) as a template, we display a correlation between synthesis conditions and pore structure of CSSHCs. CSSHCs are synthesized via a facile route including pre‑carbonization, purifying, mechanical ball-milling and high-temperature carbonization, and it is found that adjusting the secondary calcination temperature can induce the formation of closed pore structure, which is of great benefit to increase the ICE and the plateau-capacity. Besides, it is also proved that the obtained CSSHCs anodes obey a sodium storage mechanism that can be classified as “adsorption-intercalation-pore filling”, which endows SIBs with a competitive electrochemical performance. Specifically, the obtained biomass hard carbons at 1300 °C exhibits the best electrochemical performance among these anodes with the reversible capacity of as high as 270.0 mAh g−1 and a high ICE of 80.1 %, together with an excellent cycle stability (91.0 % capacity retention after 200 cycles at 0.1C, 1C = 300 mA g−1). Therefore, this study provides a significant exploration and raw material support for the further utilization of the waste biomass and sustainable development of the anode materials for the large-scale application of SIBs.

Iron-decorated N/S co-doped porous carbon for sodium-ion battery anode to achieve high initial coulombic efficiency

Hard carbon materials are preferred as anode materials for sodium-ion batteries due to their abundance, low price, and environmental friendliness. However, doping-based modification usually induces low initial coulombic efficiency (ICE), which seriously affects the practical application of carbon materials. In this work, Fe-modified N/S co-doped porous carbon is prepared using the salt template method. Fe, N, and S are uniformly distributed on the porous carbon to form an interwoven network structure, providing abundant active sites. Moreover, during the electrochemical reaction, FeNx effectively catalyzes the generation of solid electrolyte interface (SEI) film, which reduces the consumption of Na+ in the side reaction, leading to a high initial coulombic efficiency, and at the same time, the stabilized SEI film accelerates the diffusion of electrons and ions, effectively enhancing the multiplication rate performance. The NFSC exhibits a high specific capacity (371.3 mAh/g) by the co-coordination strategy and a high ICE (85.9 %). This study provides new ideas for research based on the modification of carbon materials.

Nitrogen and phosphorus co-doped hard carbon materials as high-performance anode for sodium ion batteries

Abstract The negative electrode of sodium ion batteries has always faced severe challenges in the commercialization process. To improve capacity, increase the first Coulomb efficiency, and enhance performance under high current density, we have prepared a nitrogen phosphorus co-doped hard carbon material. Phosphorus groups are doped in the material to achieve sodium storage, at the same time, coating phenolic resin for material modification. At the same time, nitrogen and carbon nanotube structures are added during the preparation process to make it have good conductivity. In order to solve the problem of low first Coulomb efficiency, adopted CMC binder and ether based electrolyte to solve the problem of excessive reaction between the negative electrode and the electrolyte during the first discharge process. In actual testing, this material has a capacity of 365 mAh g−1 and a capacity retention rate of 112% under long cycles.

Self-Assembly of Soft and Conformable Broadband Absorbing Nanocellulose-Gold Nanoparticle Composites.

Broadband light-absorbing materials are of large interest for numerous applications ranging from solar harvesting and photocatalysis to low reflection coatings. Fabrication of these materials is often complex and typically utilizes coating techniques optimized for flat and hard materials. Here, we show a self-assembly based strategy for generating robust but mechanically flexible broadband light-absorbing soft materials that can conform to curved surfaces and surface irregularities. The materials were fabricated by adsorbing large quantities of gold nanoparticles (AuNPs) on the nanofibrils of hydrated bacterial cellulose (BC) membranes by tailoring the interaction potential between the cellulose nanofibrils and the AuNPs. The highly efficient self-assembly process resulted in very dense multilayers of AuNPs on the nanofibrils, causing extensive broadening of the localized surface plasmon resonance band and a striking black appearance of the BC membranes. The nanocomposite materials showed an absorptance >96% in both the visible and the near-infrared wavelength range. The AuNP-functionalized BC membranes demonstrated excellent conformability to curved and structured surfaces and could adopt the shape of highly irregular surface structures without any obvious changes in their optical properties. The proposed self-assembly based strategy enables the fabrication of soft and conformable broadband light-absorbing nanocomposites with unique optical and mechanical properties using sustainable cellulose-based materials.

Hydrostatic Pressure‐Tuning of Opto‐Electronic and Thermoelectric Properties Half‐Heusler Alloy RhTiP With DFT Analysis

ABSTRACTUtilizing DFT along with Boltzmann transport theory, the structural, elastic, electrical, optical, and thermoelectric properties of half‐Heusler compound RhTiP have been calculated in principle to examine the pressure effect in the range of 0–40 GPa. As pressure increases, the volume and normalized lattice parameter decreased. In addition to satisfying the Born stability criterion, which ensured the compound RhTiP “natural stability,” the zero pressure elastic constants and the pressure‐dependent elastic constants are positive up to 40 GPa. The band structure computations guarantee the semiconductor nature of RhTiP, as demonstrated by the presence of electronic band gap of 1.035 eV at zero pressure. Using the Voigt‐Reuss‐Hill (VRH) averaging scheme under pressure, we have determined the values of this compound's bulk modulus , shear modulus , Young's modulus , Pugh ratio , Poisson's ratio , and anisotropy factor . Because the bulk modulus responds linearly to pressure, the material's hardness increases as pressure rises. Additionally, under pressures up to 40 GPa, the optical characteristics of RhTiP, including their reflectivity, absorptivity, conductivity, dielectric constant, refractive index, and loss function, were assessed and discussed. Furthermore, the thermoelectric properties are also studied for the materials and supports the tunning of pressure. This study provides a gateway to how the optoelectronic and transport properties of cubic RhTiP could be tuned by employing external pressure.

Hard Copper Boride with Exceptional Conductivity.

Copper and boron seldom engage in reaction at ambient pressure. The few reports on copper-doped boron compounds that exist in the literature often lack definitive stoichiometry. Here, we report successful synthesis of Cu_{2-δ}B_{25} single crystals (δ∼0.03, indicating Cu understoichiometry) via a high-pressure melting method using copper and β-rhombohedral boron as precursors. Crystals thus synthesized are characterized by a tetragonal boron sublattice, within which Cu atoms are either partially or fully situated at different interstices between B_{12} icosahedra. The crystals possess a high Vickers hardness of 26.5GPa and an unusually high electrical conductivity of 1.19×10^{5} S/m-the highest conductivity among the icosahedron-based borides. Hall measurements reveal a notable p-n conduction type transition around 30GPa. This transition, alongside the remarkable conductivity, is potentially modulated by the copper content and its valence states within the structure. The synthesis of Cu_{2-δ}B_{25} not only broadens the spectrum of hard materials but also opens new avenues for innovative modulation of electronic properties in boron-rich compounds, with promising technological implications.

Comparison of Fracture Strength of Milled and 3D-Printed Crown Materials According to Occlusal Thickness.

This study aimed to measure the fracture strengths and hardness of final restorative milled and 3D-printed materials and evaluate the appropriate crown thickness for their clinical use for permanent prosthesis. One type of milled material (group M) and two types of 3D-printed materials (groups P1 and P2) were used. Their crown thickness was set to 0.5, 1.0, and 1.5 mm for each group, and the fracture strength was measured. Vickers hardness was measured and analyzed to confirm the hardness of each material. Scanning electron microscopy was taken to observe the surface changes of the 3D-printed materials under loads of 900 and 1500 N. With increased thickness, the fracture strength significantly increased for group M but significantly decreased for group P1. For group P2, the fracture strengths for the thicknesses of 0.5 mm and 1.5 mm significantly differed, but that for 1.0 mm did not differ from those for other thicknesses. The hardness of group M was significantly higher than that of groups P1 and P2. For all thicknesses, the fracture strength was higher than the average occlusal force for all materials; however, an appropriate crown thickness is required depending on the material and component.

Investigation on growth, structural, mechanical, linear and nonlinear optical properties of DiLithium Fumarate TetraHydrate single crystal

In this work reports on the growth and characterization of semiorganic NLO single crystal of DiLithium Fumarate TetraHydrate (DLFTH) using a slow evaporation technique. The crystal structure was an orthorhombic crystal system with the centrosymmetric space group Pbcn, as demonstrated by single crystal X-ray diffraction (SCXRD) investigations. The UV–Vis-NIR spectrum is used to derive optical parameters, such as the lower cut off wavelength (277 nm) and optical energy band gap Eg = 4.98 eV. DLFTH crystals belongs to hard material category using Vickers microhardness test. From NLO studies, the nonlinear optical parameters were studied, such as the nonlinear refractive index (n2), absorption coefficient (β) and third order NLO susceptibility (χ3). The crystal has the properties of saturable absorption and self-defocusing nature. Third order NLO susceptibility (χ3) were found to be 4.14384 × 10-10esu. The higher χ3 number is due to the presence of hydrogen bonds between C-H-O and O-H-O atoms. Therefore, we confirm that it’s applicability for optical device applications.