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The analysis of the grinding mechanism of ITO conductive glass is particularly important for revealing material damage and chip formation. This article proposes the removal mechanism of brittle thin film materials during grinding based on the indentation model. And based on the thin film composite structure of ITO conductive glass, a material model in finite element simulation was established. The surface morphology and chip state of ITO conductive glass were studied through microscale grinding experiments. By comparing the simulation results, it has been proven that the ITO film is removed in a brittle fracture mode during the grinding process, while the removal mode of the glass substrate is influenced by the process parameters. The interlayer fracture between the film and substrate will affect the processing quality. [ABSTRACT FROM AUTHOR]

To investigate the effect of microscale grinding on the quality of ITO conductive glass, this paper conducted microscale grinding experiments on ITO conductive glass. The influence of process parameters on machining quality was analyzed using microgrinding force, surface roughness, and sheet resistance as indicators. Meanwhile, soda-lime glass was set as the control group to analyze the effect of ITO film. The results indicate that brittle fracture is the main removal method for ITO films, and the glass substrate exhibits two different removal methods, brittle and ductile, depending on the process parameters. The ITO thin film layer suppresses the sheet deformation of the glass substrate, increasing the grinding force and reducing the processing quality. Increasing the spindle speed, reducing the feed speed, and reducing the cutting depth can improve the machining quality. The spindle speed has a significant impact on surface roughness, while the cutting depth has a significant impact on the sheet resistance of the thin film. In addition, soda-lime glass chips mainly appear in powder and granular form, while ITO conductive glass also has flaky thin film chips generated by interlayer fracture. [ABSTRACT FROM AUTHOR]

The thermal error is a significant factor that influences the machining accuracy of machine tools, and error compensation is an economical and effective method for enhancing the accuracy of machine tools. However, establishing a precise thermal error prediction model is crucial for thermal error compensation. In this paper, the subtraction-average-based optimizer-based CNN-GRU neural network (SABO-CNN-GRU) is applied to integrated thermal error modeling. Through conducting a thermal characteristic experiment, temperature rise data and thermal error data were collected from the linear feed system of LXK300X helical groove CNC machine tool. The fuzzy c-means clustering and grey correlation analysis are employed to identify temperature-sensitive points in the linear feed system. By utilizing the temperature rise data from these sensitive points along with feed shaft thermal errors as data samples, and using the SABO algorithm to optimize the CNN-GRU prediction model, the thermal error prediction model of SABO-CNN-GRU is established. To validate its superiority and practicality, a comparative analysis is conducted with traditional thermal error prediction models based on CNN-GRU and SO-ELM. The results demonstrate that SABO-CNN-GRU model outperforms both models in terms of mean absolute error (MAE), root mean square error (RMSE), remaining prediction deviation (RPD), mean square error (MSE), and determination coefficient (R2) in accurately predicting results. Building upon this achievement, this paper develops a real-time thermal error compensation system which effectively reduces maximum thermal errors from 80.5 to 17.6 μm after implementing compensation measures. Effectively reducing the influence of thermal errors and improving the machining accuracy of machine tools. [ABSTRACT FROM AUTHOR]

To investigate the machining mechanism of silicon carbide (SiC) ceramic materials, this study utilized sintered diamond tools to perform drilling and grinding simulations on the material and developed a drilling model for SiC ceramic materials. By analyzing parameters such as surface morphology, stress, and cutting force, the material removal mechanism of SiC ceramic materials was revealed, and the effects of drilling parameters on cutting force, torque, and residual stress were studied. Experimental results indicate that during the abrasive cutting process, the hard contact behavior of irregular abrasive grains significantly affects material removal, leading to failure forms such as chip collapse, hole and groove cracking, and crack propagation. With an increase in the feed rate of the abrasive grains, the drilling force shows a certain range of growth patterns. The axial force is positively correlated with spindle speed and feed rate, with the feed rate having a more significant impact on the magnitude of the axial force. Additionally, as the feed rate increases, the torque also increases. The radial residual stress mainly manifests as residual tensile stress. [ABSTRACT FROM AUTHOR]

The nano-cutting process of metallic glass (Zr52Cu20Ni16Ni12) processed at room temperature was studied by molecular dynamics simulation in this paper. At different cutting speeds, the microstructure of metallic glass, cutting force, strain morphology of cutting zone, temperature change of cutting zone and its influence on the quality of machined surface were analyzed. The simulation results show that the cutting speed has little effect on the content of Voronoi polyhedron in the cutting area of metallic glass. The cutting force increases significantly with the increase of cutting speed. The shape of strain deformation in the cutting zone of metallic glass material is significantly affected by the cutting speed, and the influence depth of strain is deepened with the increase of cutting speed. The increase of cutting speed has a significant effect on the temperature of the cutting zone of metallic glass, and the temperature of atoms in the cutting zone increases rapidly. The cutting speed has a significant impact on the surface quality of metal glass cutting. The surface quality of metal glass cutting becomes worse with the increase of cutting speed. In particular, the initial stage of plastic deformation in metal glass cutting process is simulated and analyzed, and the formation and evolution of its shear band and free volume are simulated and studied. [ABSTRACT FROM AUTHOR]

The nano cutting process of Zr-based amorphous alloy was simulated by molecular dynamics simulation in this paper. Through the research on the changing rule of cutting force in nano cutting of Zr-based amorphous alloy, it is found that the cutting force increases continuously, and the cutting rate is large at the initial stage of nano cutting, which may be related to the shear deformation of the atomic clusters or atomic clusters in the shear transition zone. The effect of cutting tool rake angle on nano cutting process for Zr-based amorphous alloy was studied. The simulation results show that the cutting force decreases with the increase of the rake angle of the cutting tool, and the friction coefficient between the rake face and the chip also decreases slightly. With the increase of the rake angle of the cutting tool, the pushing effect of the tool on the Zr-based amorphous alloy chip and the overall bending of the chip are weakened, leading to the increase of the chip height. The number of high-temperature atoms in the Zr-based amorphous alloy workpiece also decreases with the increase of the tool rake angle, and the cutting temperature distribution on the workpiece diffuses to the interior of the workpiece with the tool fillet as the center. [ABSTRACT FROM AUTHOR]

Zr-based bulk metallic glass is an amorphous alloy. In order to study the burr problem in the groove milling process of Zr-based bulk metallic glass, the milling force in the process is studied experimentally. Then the effect of milling parameters on the burr of Zr-based bulk metallic glass was studied, and the relationship between milling force and burr was analyzed. In order to further study the milling burr of amorphous alloy, under the same test parameters, the single crystal alloy material (nickel base single crystal superalloy DD5) and the traditional polycrystalline metal material (304 stainless steel) were selected for comparative test and analysis. The results show that Zr-based bulk metallic glass has good groove milling machinability. The test results provide some experimental basis for groove milling of Zr-based bulk metallic glass. [ABSTRACT FROM AUTHOR]

In order to study the milling machinability of Zr-based bulk metallic glass, a comparative experimental study on the surface roughness of the milling groove bottom surface for Zr-based bulk metallic glass was carried out in this paper. Through different processing materials, milling tools with different coatings, milling tools with different geometric parameters, and different processing conditions, a large number of comparative tests were carried out on the surface roughness of the milling groove bottom surface for Zr-based bulk metallic glass. The surface roughness values of the milling groove bottom surface are compared, studied, and analyzed from many angles (surface roughness Sa, Sq, Sz, Ssk, and Sku). The test results show that Zr-based bulk metallic glass has good milling machinability. It can obtain a low surface roughness value through the processing conditions and methods used in the test. The research content of this paper provides experimental basis for groove milling of Zr-based bulk metallic glass. At the same time, it also provides a strong test basis for the manufacture of Zr-based bulk metallic glass parts. [ABSTRACT FROM AUTHOR]

The effect of milling parameters on chip shape and chip morphology for Zr-based bulk metallic glass was studied in this paper. The milling groove experiments of Zr-based bulk metallic glass (Zr-based BMG) (Zr52Cu17.5Ti16Ni12Nb2.5) were conducted by using a JX-1A ultra-precision machine tool. In order to study the milling quality and milling characteristics of Zr-based bulk metallic glass, it is very important to study the chip shape and chip morphology. In this paper, firstly, the temperature field distribution of Zr-based bulk metallic glass in milling process was simulated by finite element method, and the milling temperature and its distribution at different cutting speeds were obtained. Then the effect of different milling parameters on chip shape and chip morphology was studied, and the reason of the change was analyzed. Then the influence of milling cutters with different geometric parameters on the chip shape and chip morphology of Zr-based bulk metallic glass was also studied. At last, under the same milling conditions, the chip shape and chip morphology of traditional polycrystalline metal materials, monocrystalline metal alloy materials, high-entropy alloy which is in amorphous system, and Zr-based bulk metallic glass were compared. It provides theoretical and experimental basis for the groove milling technology of Zr-based bulk metallic glass. [ABSTRACT FROM AUTHOR]

The milling groove experiments of Zr-based bulk metallic glass (Zr-based BMG) (Zr52Cu17.5Ti16Ni12Nb2.5) are conducted by using an ultra-precision lathe. In order to study the milling groove flank contour accuracy in mesoscale groove milling for Zr-based bulk metallic glass component, the milling force and the flank contour shape were investigated by single-factor experiment. The effect of milling process parameters of Zr-based bulk metallic glass materials on the milling force and the flank contour profile of milling groove were obtained, and the relationship between flank contour profile of milling groove and milling force was also obtained. The flank contour profile of milling groove for Zr-based bulk metallic glass is analyzed theoretically. The effect of milling experimental parameters on the deviation between the actual flank contour profile of milling groove and the theoretical flank contour profile of milling groove is analyzed and summarized through the experiment. [ABSTRACT FROM AUTHOR]

Tin carbon nanofibers were prepared by electrospinning and carbonization as flexible and independent supercapacitor materials. Sn/CNFs, Sn/SnO/CNFs, and SnO2/CNFs were prepared by different carbonization processes. The specific capacitances at 0.5 A g−1 were 761.39 F g−1, 712.29 F g−1, and 589.78 F g−1, respectively. The composite nanofibers were characterized by SEM, XPS, TEM, XRD, and Raman spectroscopy. It was found that tin nanoparticles were well dispersed in carbon nanofibers and no aggregated crystalline phase was formed. These results showed that Sn/CNFs was superior to Sn/SnO/CNFs and SnO2/CNFs in electrochemical performance of supercapacitors. In addition, a very stable cycle stability had been achieved. Even after 10,000 charge-discharge cycles, Sn/CNFs still maintain excellent specific capacitance of up to 114% of its initial performance. Moreover, Sn/CNFs//CNFs was assembled as a flexible all-solid-state asymmetric supercapacitor (ASC) with the energy density of 57.18 Wh kg−1 at a power density of 374.97 W kg−1. [ABSTRACT FROM AUTHOR]

Carbon nanofiber-based amorphous cobalt oxide (CoxOy/CNFs) embedded with Ag have been prepared by a simple electrospinning technique followed by heat treatment. Because the composite material prepared by this method showed good flexibility, addition of a conductive agent and binder is not required for use as an electrode material in supercapacitors. The Co-Ag/CNFs composite materials exhibited remarkably improved electrical conductivity and specific capacitance with good cycling stability in comparison with electrodes based on CoxOy/CNFs, owing to the presence of Ag; For instance, the Co-Ag/CNFs(2) composite electrode exhibited specific capacitance of 698 F g−1 at 1 A g−1 and good cycling stability with ∼ 81.1% capacitance retention over 3000 cycles. The composite materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD) analysis, Raman spectra, and thermogravimetric analysis (TGA), confirming successful combination of the amorphous cobalt oxide and silver metal element with the carbon nanofibers. [ABSTRACT FROM AUTHOR]

In this paper, high-capacity supercapacitor material (Fe-Nx/CNFs) synthesized by electrospinning a metal complex in PAN/DMF solution with different temperatures was presented. Moreover, nitrogen doping (N-doping in short) has been used to tailor the properties of carbon nanofibers and rendered its potential use for capacitor as an effective way. The structural and morphological properties of the Fe-Nx/CNFs were fully characterized and the carbonation temperature of the Fe-Nx/CNFs precursor was optimized. Compared with the pure carbon nanofiber, the annealing temperature of optimized Fe-Nx/CNFs composites electrode material was 550 °C. Fabricating the binder-free iron-based electrode exhibited a higher capacitance of 629 F g−1 at the current density of 1 A g−1 in 4 mol L−1 aqueous KOH electrolyte. Meanwhile, a cycling stability of 97% capacitance retention after cycling 2500 at 5 A g−1 was maintained. This outstanding performance was attributed to the formation of the Fe-N bond and N-doped carbon nanofibers that effectively facilitates electronic transport. Therefore, carbon nanofibers, wherein nitrogen-doped metal (iron) center, exhibited high performance as supercapacitors. [ABSTRACT FROM AUTHOR]

The composite materials, carbon nanofibers-based cobalt oxide and Ag (CoxO-Ag/CNFs) were fabricated through a facile electrospinning method followed by calcination. They were Co2+-Ag/CNFs, Co2+@Co3+-Ag/CNFs. And the Co2+@Co3+-Ag/CNFs sample was obtained through transform Co2+-Co3+ partially by the catalytic oxidation performance of silver, instead of the traditional high-temperature calcination process. Meanwhile, the high conductive of Ag can promote the transportation of electrons and ions between the electrode and electrolyte. The flexible composite materials as free-standing and additive-free film electrodes for supercapacitors. In virtue of the presence of Ag, the composite materials have better conductivity and supercapacitor performance than Co/CNFs-based electrode. Interestingly, the sample of Co2+-Ag/CNFs has a higher capacitors than Co2+@Co3+-Ag/CNFs sample, that indicates the supercapacitor performance has an important relationship with the valence state of cobalt. [ABSTRACT FROM AUTHOR]

One dimensional carbon nanofibers embedded amorphous cobalt oxide with high electrochemical performances were successfully prepared by electrospinning Co(NO) in PAN/DMF solution followed by a high-temperature heat treatment process. The different molar ratio of AN/Co(NO) were synthesis. The optimized Co/CNFs(30), in which the molar ratio of AN/Co(NO) was 30/1, exhibited a specific capacitance of 1096 F g at 1 A g and almost no decay in specific capacitance after cycling 2500 times at 5 A g. The Co/CNFs were characterized by scanning electron microscopy, X-ray diffraction, Raman, transmission electron microscopy, X-ray photoelectron spectroscopy, thermal-gravity-analysis and the N adsorption-desorption. The result showed that cobalt element was successfully dispersed in the carbon nanofibers with an amorphous state. [ABSTRACT FROM AUTHOR]

The space charge layer (SCL) is generally considered one of the origins of the sluggish interfacial lithium-ion transport in all-solid-state lithium-ion batteries (ASSLIBs). However, in-situ visualization of the SCL effect on the interfacial lithium-ion transport in sulfide-based ASSLIBs is still a great challenge. Here, we directly observe the electrode/electrolyte interface lithium-ion accumulation resulting from the SCL by investigating the net-charge-density distribution across the high-voltage LiCoO2/argyrodite Li6PS5Cl interface using the in-situ differential phase contrast scanning transmission electron microscopy (DPC-STEM) technique. Moreover, we further demonstrate a built-in electric field and chemical potential coupling strategy to reduce the SCL formation and boost lithium-ion transport across the electrode/electrolyte interface by the in-situ DPC-STEM technique and finite element method simulations. Our findings will strikingly advance the fundamental scientific understanding of the SCL mechanism in ASSLIBs and shed light on rational electrode/electrolyte interface design for high-rate performance ASSLIBs. Understanding the effect of the space charge layer (SCL) in all-solid-state lithium-ion batteries is challenging due to lack of direct experimental observations. Here the authors visualize the SCL using an in-situ DPC-STEM imaging technique, based on which they further introduce a built-in electric field to suppress its formation. [ABSTRACT FROM AUTHOR]