Dynamic Calibration of the Cutting Temperature Sensor of NiCr/NiSi Thin-film Thermocouple

In high-speed cutting, natural thermocouple, artificial thermocouple and infrared radiation temperature measurement are usually adopted for measuring cutting temperature, but these methods have difficulty in measuring transient temperature accurately of cutting area on account of low response speed and limited cutting condition. In this paper, NiCr/NiSi thin-film thermocouples（TFTCs） are fabricated according to temperature characteristic of cutting area in high-speed cutting by means of advanced twinned microwave electro cyclotron resonance（MW-ECR） plasma source enhanced radio frequency（RF） reaction non-balance magnetron sputtering technique, and can be used for transient cutting temperature measurement. The time constants of the TFTCs with different thermo-junction film width are measured at four kinds of sampling frequency by using Ultra-CFR short pulsed laser system that established. One-dimensional unsteady heat conduction model is constructed and the dynamic performance is analyzed theoretically. It can be seen from the analysis results that the NiCr/NiSi TFTCs are suitable for measuring transient temperature which varies quickly, the response speed of TFTCs can be obviously improved by reducing the thickness of thin-film, and the area of thermo-junction has little influence on dynamic response time. The dynamic calibration experiments are made on the constructed dynamic calibration system, and the experimental results confirm that sampling frequency should be larger than 50 kHz in dynamic measurement for stable response time, and the shortest response time is 0.042 ms. Measurement methods and devices of cutting heat and cutting temperature measurement are developed and improved by this research, which provide practical methods and instruments in monitoring cutting heat and cutting temperature for research and production in high-speed machining.

Design of Cold-Junction Compensation and Disconnection Detection Circuits of Various Thermocouples and Implementation of Multi-Channel Interfaces Using Them-A Secondary Publication

Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain.

Research on dynamic error compensation for an armored K type thermocouple

A new method was proposed, in which a high-power CO2 laser modulated by high frequency was used as the driv- ing source to heat up a surface-temperature sensor. The continual beam and the pulsed beam sent out by the same laser could be used in the same system to carry on the static calibration of the radiation thermometer and the dynamic calibration of the temperature sensor to be checked. The frequency-response characteristics of high-speed radiation thermometer surpassed that of the temperature sensor, therefore it could be used as the reference value to calibrate the latter and let system error be cor- rected. Differences in the environment of the sensor installing and the error caused by the change of thermo-physical proper- ty could be avoided. Thus, the difficult problem of traceable dynamic calibration of temperature was solved. In experiment, to obtain the frequency characteristics of the thermocouple and the dynamic performance of the K type thermocouple, which could compensate the dynamic characteristics of the sensor, the sensor was dynamically corrected by using the method, and then the mathematical model was established.

Research on measuring time constant of NANMAC thermocouple

The theory for measuring the time constant of thermocouple was introduced, and the method for measuring the time constant of NANMAC thermocouple by using dynamic calibration system of transient surface temperature sensor was proposed. In this system, static and dynamic calibrations were conducted for infrared detectors and thermocouples, and then both temperature-time curves were obtained. Since the frequency response of infrared detector is superior to that of calibrat- ed thermocouple, the values measured by infrared detectors are taken as true values. Through dividing the values measured with thermocouples by those with infrared detectors, a normalized curve was obtained, based on which the time constant of thermocouple was measured. With this method, the experiments were carried out with NANMAC thermocouple to obtain its time constant. The results show that the method for measuring the time constant is feasible and the dynamic calibration of thermocouples can be achieved at microsecond and millisecond level. This research has a certain reference value for research and application of NANMAC thermocouple temperature sensor.

Improving the Quality of Thermocouple Wire Made of Platinum-rhodium Alloys

For the manufacture of S-type thermocouple the so-called thermocouple wire of platinum and platinum-rhodium alloy is used.One of the main technical requirements for the quality of the wire,according to State Standard of Russia(GOST 10821),is the uniformity of its largest thermoelectric force(Thermo-emf) in the length different sections.It was found that a determining impact on the uniformity of the wire thermo-emf is the distribution of rhodium along the length of the wire.The impact of platinum-rhodium melt crystallization conditions on the inhomogeneity of wire manufactured from it.It was suggested that the chemical inhomogeneity of the wire is related to the liquation phase of platinum-rhodium alloy.

EMF CHANGES MADE BY COLD DRAWING AND HEATING TREATMENT IN TYPE K HEAVY-GAUGE SHEATHED THERMOCOUPLE CABLES

The electromotive force (EMF) changes in type K heavy gauge sheathed thermocouple cables was investigated. To cope with this discrepancy owing to EMF steep reduction and understand the difference between type K heavy gauge sheathed thermocouple cables and small ones, the affects of EMF from sheath pipe, drawing times, annealing temperature, annealing time and annealing way were mainly studied and appropriately analyzed. The results show the change in the thermal EMF is related with the residual stress and crystal defects, which are imparted by cold work during manufacture. The affects of cold work can be removed by annealing. Finally, a feasible way of fabricating heavy gauge sheathed thermocouples was suggested according to practical situation.

The Linearized Design Of Thermocouple Sensor

There are large errors of linear measurement when the thermocouple measure temperature as temperature sensor.In order to improve the measurement precision,the sensor cold junction compensation and nonlinear compensation are usually needed.For the circumstances that the cold junction’s temperature is determinate,there is biggish nonlinear between thermoelectric power and temperature signals of the thermocouple sensor’s output.In order to solve the problem,this paper proposed a practical method of linear compensation,introduced the principle of linear compensation and gave the corresponding compensation circuit and circuit analysis.This circuit has the characteristic of simpleness,high reliability,small linear error and so on.

THERMOCOUPLE USED FOR TEMPERATURE MEASUREMENT OF ALUMINIUM CELLS BY DYNAMIC METHOD

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Erosion thermocouple temperature acquisition system

Aiming at high requirements of temperature measurement system in high temperature,high pressure,highly corrosive and other special environments,a temperature acquisition system based on field-programmable gate array(FPGA) which is the controller of the system is designed.Also a Flash memory is used as the memory and an erosion thermocouple is used as sensor of the system.Compared with the traditional system using complex programmable logic device(CPLD)and microcontroller unit(MCU)as the main body,this system has some advantages,such as short response time,small volume,no loss of data once power is off,high precision,stability and reliability.And the sensor of the system can be reused.In this paper,boiling water experiment is used to verify accuracy of the system.The millisecond level signal from firecrackers is for verifying the stability and fast response characteristics of the system.The results of experiment indicate that the temperature measurement system is more suitable for the field of explosion and other environments which have high requirements for the system.

Proposal and Verification of Simultaneous Measurement Method for Three Thermoelectric Properties with Film-Type Thermocouple Probe

A new simultaneous measurement method for the measurement of the three thermoelectric properties with a film-type thermocouple probe was proposed. Seebeck coefficient was measured using the steady-state condi-tion of the differential method. The electrical resistivity was measured us-ing the four-probe method and the thermal diffusivity is measured using the periodic heating method. The effectiveness of the proposed method was verified using constantan as a reference material. After describing the effectiveness of the method, the measurement of three thermoelectric properties of Bi0.3Sb1.7Te3, which is a thermoelectric material, was per-formed.

Heterojunction-engineered carrier transport in elevated-metal metal-oxide thin-film transistors

This study investigates the carrier transport of heterojunction channel in oxide semiconductor thin-film transistor(TFT)using the elevated-metal metal-oxide(EMMO)architecture and indium−zinc oxide(InZnO).The heterojunction band diagram of InZnO bilayer was modified by the cation composition to form the two-dimensional electron gas(2DEG)at the interface quantum well,as verified using a metal−insulator−semiconductor(MIS)device.Although the 2DEG indeed contributes to a higher mobility than the monolayer channel,the competition and cooperation between the gate field and the built-in field strongly affect such mobility-boosting effect,originating from the carrier inelastic collision at the heterojunction interface and the gate field-induced suppression of quantum well.Benefited from the proper energy-band engineering,a high mobility of 84.3 cm2·V^(−1)·s^(−1),a decent threshold voltage(V_(th))of−6.5 V,and a steep subthreshold swing(SS)of 0.29 V/dec were obtained in InZnO-based heterojunction TFT.

Indispensable gutter layers in thin-film composite membranes for carbon capture

Industrial thin-film composite(TFC)membranes achieve superior gas separation properties from high-performance selective layer materials,while the success of membrane technology relies on high-performance gutter layers to achieve production scalability and low-cost manufacturing.However,the current literature predominantly focuses on the design of polymer architectures to obtain high permeability and selectivity,while the art of fabricating gutter layers is usually safeguarded by industrial manufacturers and appears lackluster to academic researchers.This is the first report aiming to provide a comprehensive and critical review of state-of-the-art gutter layer materials and their design and modification to enable TFC membranes with superior separation performance.We first elucidate the importance of the gutter layer on membrane performance through modeling and experimental results.Then various gutter layer materials used to obtain high-performance composite membranes are critically reviewed,and the strategies to improve their compatibility with the selective layer are highlighted,such as oxygen plasma treatment,polydopamine deposition,and surface grafting.Finally,we present the opportunities of the gutter layer design for practical applications.

Low-Volatile Binder Enables Thermal Shock-Resistant Thin-Film Cathodes for Thermal Batteries

Manufacturing thin-film components is crucial for achieving high-efficiency and high-power thermal batteries(TBs).However,developing binders with low-gas production at the operating temperature range of TBs(400-550°C)has proven to be a significant challenge.Here,we report the use of acrylic acid derivative terpolymer(LA136D)as a low-volatile binder for thin-film cathode fabrication and studied the chain scission and chemical bondbreaking mechanisms in pyrolysis.It is shown LA136D defers to randomchain scission and cross-linking chain scission mechanisms,which gifts it with a low proportion of volatile products(ψ,ψ=39.2 wt%)at even up to 550°C,well below those of the conventional PVDF(77.6 wt%)and SBR(99.2 wt%)binders.Surprisingly,LA136D contributes to constructing a thermal shock-resistant cathode due to the step-by-step bond-breaking process.This is beneficial for the overall performance of TBs.In discharging test,the thin-film cathodes exhibited a remarkable 440%reduction in polarization and 300%enhancement in the utilization efficiency of cathode materials,while with just a slight increase of 0.05 MPa in gas pressure compared with traditional“thick-film”cathode.Our work highlights the potential of LA136D as a low-volatile binder for thin-film cathodes and shows the feasibility of manufacturing high-efficiency and high-power TBs through polymer molecule engineering.

Implementation of sub-100 nm vertical channel-all-around(CAA) thin-film transistor using thermal atomic layer deposited IGZO channel

In-Ga-Zn-O(IGZO) channel based thin-film transistors(TFT), which exhibit high on-off current ratio and relatively high mobility, has been widely researched due to its back end of line(BEOL)-compatible potential for the next generation dynamic random access memory(DRAM) application. In this work, thermal atomic layer deposition(TALD) indium gallium zinc oxide(IGZO) technology was explored. It was found that the atomic composition and the physical properties of the IGZO films can be modulated by changing the sub-cycles number during atomic layer deposition(ALD) process. In addition, thin-film transistors(TFTs) with vertical channel-all-around(CAA) structure were realized to explore the influence of different IGZO films as channel layers on the performance of transistors. Our research demonstrates that TALD is crucial for high density integration technology, and the proposed vertical IGZO CAA-TFT provides a feasible path to break through the technical problems for the continuous scale of electronic equipment.

Generation of broadband polarization-orthogonal photon pairs via the dispersion-engineered thin-film lithium niobate waveguide

Broadband photon pairs are highly desirable for quantum metrology,quantum sensing,and quantum communication.Such sources are usually designed through type-0 phase-matching spontaneous parametric down-conversion(SPDC)that makes the photon pairs hard to separate in the frequency-degenerate case and thus limits their applications.In this paper,we design a broadband frequency-degenerate telecom-band photon pair source via the type-II SPDC in a dispersion-engineered thin-film lithium niobate waveguide,where the polarization modes of photon pairs are orthogonal and thus are easily separated deterministically.With a 5-mm-long waveguide,our design can achieve a bandwidth of 5.56 THz(44.8 nm),which is 8.6 times larger than that of the bulk lithium niobate,and the central wavelength can be flexibly adjusted.Our design is a promising approach towards high-quality integrated photon sources and may have wide applications in photonic quantum technologies.

Numerical Study and Optimization of CZTS-Based Thin-Film Solar Cell Structure with Different Novel Buffer-Layer Materials Using SCAPS-1D Software

This study explored the performances of CZTS-based thin-film solar cell with three novel buffer layer materials ZnS, CdS, and CdZnS, as well as with variation in thickness of buffer and absorber-layer, doping concentrations of absorber-layer material and operating temperature. Our aims focused to identify the most optimal thin-film solar cell structure that offers high efficiency and lower toxicity which are desirable for sustainable and eco-friendly energy sources globally. SCAPS-1D, widely used software for modeling and simulating solar cells, has been used and solar cell fundamental performance parameters such as open-circuited voltage (), short-circuited current density (), fill-factor() and efficiency() have been optimized in this study. Based on our simulation results, it was found that CZTS solar cell with Cd0.4Zn0.6S as buffer-layer offers the most optimal combination of high efficiency and lower toxicity in comparison to other structure investigated in our study. Although the efficiency of Cd0.4Zn0.6S, ZnS and CdS are comparable, Cd0.4Zn0.6S is preferable to use as buffer-layer for its non-toxic property. In addition, evaluation of performance as a function of buffer-layer thickness for Cd0.4Zn0.6S, ZnS and CdS showed that optimum buffer-layer thickness for Cd0.4Zn0.6S was in the range from 50 to 150nm while ZnS offered only 50 – 75 nm. Furthermore, the temperature dependence performance parameters evaluation revealed that it is better to operate solar cell at temperature 290K for stable operation with optimum performances. This study would provide valuable insights into design and optimization of nanotechnology-based solar energy technology for minimizing global energy crisis and developing eco-friendly energy sources sustainable and simultaneously.

Numerical Analysis on the Effect of n-Si on Cu(In, Ga)Se2 Based Thin-Films for High-Performance Solar Cells by 1D-SCAPS

We report the performances of a chalcopyrite Cu(In, Ga)Se2 CIGS-based thin-film solar cell with a newly employed high conductive n-Si layer. The data analysis was performed with the help of the 1D-Solar Cell Capacitance Simulator (1D-SCAPS) software program. The new device structure is based on the CIGS layer as the absorber layer, n-Si as the high conductive layer, i-In2S3, and i-ZnO as the buffer and window layers, respectively. The optimum CIGS bandgap was determined first and used to simulate and analyze the cell performance throughout the experiment. This analysis revealed that the absorber layer’s optimum bandgap value has to be 1.4 eV to achieve maximum efficiency of 22.57%. Subsequently, output solar cell parameters were analyzed as a function of CIGS layer thickness, defect density, and the operating temperature with an optimized n-Si layer. The newly modeled device has a p-CIGS/n-Si/In2S3/Al-ZnO structure. The main objective was to improve the overall cell performance while optimizing the thickness of absorber layers, defect density, bandgap, and operating temperature with the newly employed optimized n-Si layer. The increase of absorber layer thickness from 0.2 - 2 µm showed an upward trend in the cell’s performance, while the increase of defect density and operating temperature showed a downward trend in solar cell performance. This study illustrates that the proposed cell structure shows higher cell performances and can be fabricated on the lab-scale and industrial levels.

Equivalent Circuit Analysis of an RF Integrated Inductor with Ferrite Thin-Film

An equivalent circuit for a novel RF integrated inductor with ferrite thin-film is derived. The enhancement of the magnetic ferrite thin-film on the inductance （L） and quality factor （Q） of the inductor is analyzed. Circuit element parameters are extracted from RF measurements. Compared with the reference air-core inductor without magnetic film, L and Q of the ferrite thin-film inductor are 17% and 40% higher at 2GHz,respectively. Both the equivalent circuit analysis and test results demonstrate significant enhancement of the performance of RF integration inductors by ferrite thin-film integration.

Cutting force measurement based on tool embedded Ni-chrome thin-film micro-sensors

Cutting force measurement has become a crucial activity for enhancing machining process performance. This paper described the design and fabrication of embedded Ni-chrome thin-film micro-sensors in tool holders to measure the cutting force in machining operations. A Ni-chrome thin-film sensor device is embedded within a substrate structure through a dy- namic brazing process, which consists of a Ti6A14V substrate, a nickel-chromium thin-film sensor and an alumina insulating layer. The Wheatstone bridge which consists of four sensors would produce the output voltage when the thin film caused de- formation by the cutting forces. The relationship between input and output voltages was theoretically analyzed. According- ly, an in-process cutting force measurement system is established. The results show that the thin-film sensor had good lineari- ty and less mutual interference, and it is suitable for all kinds of turning forces under the measurement conditions.

Substrate matters:The influences of substrate layers on the performances of thin-film composite reverse osmosis membranes

Thin-film composite(TFC) reverse osmosis(RO) membranes are playing the dominating role in desalination.Tremendous efforts have been put in the studies on the polyamide selective layers. However, the effect of the substrate layers is far less concerned. In this review, we summarize the works that consider the impacts of the substrates, including pore sizes, surface hydrophilicity, on the processes of interfacial polymerization and consequently on the morphologies of the active layers and on final RO performances of the composite membranes. All the works indicate that the pore sizes and surface hydrophilicity of the substrate evidently influence the RO performances of the composite membranes. Unfortunately, we find that the observations and understandings on the substrate effect are frequently varied from case to case because of the lack of substrates with uniform pores and surface chemistries. We suggest using track-etched membranes or anodized alumina membranes having relatively uniform pores and functionalizable pore walls as model substrates to elucidate the substrate effect.Moreover, we argue that homoporous membranes derived from block copolymers have the potential to be used as substrates for the large-scale production of high-performances TFC RO membranes.