载人潜水器材料技术发展现状

载人潜水器是探索海底资源、执行多种海底任务的必要设备,载人舱球壳是载人潜水器关键部件,必须使用高比强、高韧性的材料以保证它具有足够的有效载重和良好的安全性。同其它船用金属材料相比,钛合金比强度高,非常适合用于建造潜深3000m以上载人潜水器载人舱球壳,而载人舱球壳用钛合金的发展必将促进我国载人潜水器的研制和国产化进程。总结了目前国内外在载人舱球壳材料方面的研究和应用进展,对国产新型Ti6321合金进行了详细介绍。     

工业辐射温度计的辐射源尺寸效应（SSE）测量

本文给出了直接法测量工业用辐射温度计SSE的计算公式和SSE对测温结果影响的修正公式。建立直接法测量系统,对几种不同型号的被测辐射温度计的测量结果表明,SSE整体上随辐射源尺寸的增大而增加。但在源尺寸较小时SSE变化率较大,随着源尺寸的增大,SSE的变化率逐渐较小,趋于平缓。辐射温度计的校准应尽量选择与测温对象尺寸相近的辐射源直径。否则,精密测温应用需考虑SSE修正。     

测量距离影响辐射温度计检定结果的实验研究

针对测量距离对辐射温度计检定结果的影响进行了实验研究，给出了几种所选择的常用的辐射温度计的实验数据和分析图表。确定了辐射温度计的最佳测量距离是在离开黑体辐射源靶面0.3~0.5 m范围内。     

Size-of-source Effect in Infrared Thermometers with Direct Reading of Temperature

The size-of-source effect (SSE) for six infrared (IR) thermometers with direct reading of temperature was measured in this work. The alternative direct method for SSE determination, where the aperture size is fixed and the measurement distance is varied, was used in this study. The experimental equivalence between the usual and the alternative direct methods is presented. The magnitudes of the SSE for different types of IR thermometers were investigated. The maxima of the SSE were found to be up to 5 %, 8 %, and 28 % for focusable, closed-focus, and open-focus thermometers, respectively. At \(275\,^{\circ }\hbox {C}\), an SSE of 28 % corresponds to \(52\,^{\circ }\hbox {C}\), indicating the severe effect on the accuracy of this type of IR thermometer. A method to realize the calibration conditions used by the manufacturer, in terms of aperture size and measurement distance, is discussed and validated by experimental results. This study would be of benefit to users in choosing the best IR thermometer to match their work and for calibration laboratories in selecting the technique most suitable for determining the SSE.     

红外测温仪概述

本文就红外测温仪的特点、工作原理、分类、性能、选择以及使用红外测温仪主要考虑的注意事项作出简单的概述,并对红外测温仪的应用举例说明。     

玻璃液体温度计检定技术

玻璃液体温度计目前应用最广泛的温度测量仪器之一,为确保该类仪表测量时的准确可靠,探讨玻璃液体温度计的检定技术十分重要。     

Monochromator-Based Absolute Calibration of Radiation Thermometers

A monochromator integrating-sphere-based spectral comparator facility has been developed to calibrate standard radiation thermometers in terms of the absolute spectral radiance responsivity, traceable to the PTB cryogenic radiometer. The absolute responsivity calibration has been improved using a 75 W xenon lamp with a reflective mirror and imaging optics to a relative standard uncertainty at the peak wavelength of approximately 0.17 % (k = 1). Via a relative measurement of the out-of-band responsivity, the spectral responsivity of radiation thermometers can be fully characterized. To verify the calibration accuracy, the absolutely calibrated radiation thermometer is used to measure Au and Cu freezing-point temperatures and then to compare the obtained results with the values obtained by absolute methods, resulting in T ? T ₉₀ values of +52 mK and ?50 mK for the gold and copper fixed points, respectively.     

Calibration of Contact Surface Thermometers

Some of the national metrology institutes (NMIs) have developed devices which generate a standard surface temperature under conditions which resemble, as closely as possible, those encountered during the routine use of surface sensors. Several comparisons of measurements among European NMIs, coordinated by MKEH, were undertaken in order to validate the methods used and the reference conditions. The characteristics of the reference surface significantly influence the measurement error, as its temperature, inclination and thermophysical properties. This paper presents a method of determining a correction function, containing the effects of these factors. The measurements have been taken in the temperature range from \(100\,^{\circ }\hbox {C}\) to \(500\,^{\circ }\hbox {C}\), with a specific sensor having an inflexible head. The technique developed of MKEH is suitable for quantifying the effect of the above parameters, optimizing the surface temperature measurements in this regard.     

Thermometers in Low Magnetic Fields

In this article the effect of low amplitude DC magnetic fields on different types of thermometers is discussed. By means of a precision water-cooled electromagnet, the effect of a magnetic field on platinum resistance thermometers, thermistors, and type T, J, and K thermocouples was investigated, while thermometers were thermally stabilized in thermostatic baths. Four different baths were used for temperatures from 77 K (?196 °C) to 353 K (80 °C): liquid nitrogen bath (nitrogen boiling point at atmospheric pressure), ice-point bath, room-temperature air bath, and hot-water bath. The generated DC magnetic field of high relative precision (2 × 10^?4 at 1 T, 4 × 10^?5 short-term stability) and high relative uniformity (2 × 10^?5 over 1 cm², 10 mm gap) had a magnetic flux density of 1 T in the center of the gap between the magnet pole caps. The results indicate a magnetic effect of up to 100 mK due to a 1 T magnetic field for the types of thermocouples composed of ferromagnetic materials (Fe, Cr, Ni). For platinum resistance thermometers, thermistors, and non-magnetic type T thermocouples, the detected magnetic effect was weaker, i.e., under 10 mK.     

Calculated Uncertainty of Temperature Due to the Size-of-Source Effect in Commercial Radiation Thermometers

The article evaluates the uncertainty in the temperature indicated by a radiation thermometer with a direct readout in temperature, due to the uncertainty in measuring the size-of-source effect (SSE) by the so-called “direct method.” Radiation thermometers of this type are the ones most frequently used in practice. The uncertainty of the SSE characteristic is usually not a useful quantity to report to users of commercial radiation thermometers. Instead, they would prefer to know the uncertainty in the measured temperature that results from the uncertainty of the SSE characteristic, and this will be the result of our analysis. The user of a direct reading radiation thermometer will be able to take into account the uncertainty of temperature due to the SSE, if a target with known dimensions is measured. The uncertainty in temperature due to the SSE of analyses based on Planck’s law and its approximation, Wien’s law is compared.     

Perturbations From Ducts on the Modes of Acoustic Thermometers

We examine the perturbations of the modes of an acoustic thermometer caused by circular ducts used either for gas flow or as acoustic waveguides coupled to remote transducers. We calculate the acoustic admittance of circular ducts using a model based on transmission line theory. The admittance is used to calculate the perturbations to the resonance frequencies and half-widths of the modes of spherical and cylindrical acoustic resonators as functions of the duct’s radius, length, and the locations of the transducers along the duct''s length. To verify the model, we measured the complex acoustic admittances of a series of circular tubes as a function of length between 200 Hz and 10 kHz using a three-port acoustic coupler. The absolute magnitude of the specific acoustic admittance is approximately one. For a 1.4 mm inside-diameter, 1.4 m long tube, the root mean square difference between the measured and modeled specific admittances (both real and imaginary parts) over this frequency range was 0.018. We conclude by presenting design considerations for ducts connected to acoustic thermometers.     

An Attempt to Simplify the Determination or the Size-of-Source Effect in Radiation Thermometers

The knowledge of \(\sigma _{d}\), the parameter that measures the size-of-source effect of a radiation thermometer, as a function of the diameter d of a radiation source is mandatory to estimate the appropriate corrections to temperature values measured when aiming to radiation sources of different sizes. To obtain \(\sigma _{d}\) as a function of d is a complicated task because there is no universally recognized mathematical function that relates them. The direct method to evaluate \(\sigma _{d}\) usually requires a radiation source of appropriate size and a set of many diaphragms with increasing diameter. How good is the approximation to \(\sigma _{d}\) estimated in this way depends on the number of diaphragms used. To reduce the time and cost to evaluate \(\sigma _{d}\), it is desirable to have methods that provide good approximations with a reduced number of diaphragms. In this paper, we present a method to obtain an approximation to \(\sigma _{d}\) as a function of d with a limited number of diaphragms. When using this method, deviations of less than \(1\;{^{\circ }}\hbox {C}\) are obtained when measuring radiance temperatures of \(500\;{^{\circ }}\hbox {C}\), between the measured temperatures and those calculated from values of \(\sigma _{d}\). We also propose a simple equation to interpolate approximated values of \(\sigma _{d}\) for those diameters between those used in its evaluation, but a limitation is that \(\sigma _{d}\) must be bigger than 0.98.     

发射率对辐射温度计检定结果的影响分析

在环境温度一定情况下,主要通过计算黑体辐射源发射率、辐射温度计发射率设定分别对特定响应波长辐射温度计测量结果修正值的大小,分析和讨论了在计量检定工作中发射率对辐射温度计测量结果的影响大小,并阐述了在结果计算中对它们进行修正的必要性和重要性。     

浅谈红外测温仪在线温度校准

本文讲述在线红外测温仪测量温度的准确与否将直接影响烟丝的内在质量,为了保证烟丝的工艺质量必须对红外测温仪进行现场校准。     

Tantalum Thin-Film Superconducting Transition Edge Thermometers

Sputter deposited Ta thin films make excellent superconducting transition edge temperature sensors. Depending on film thickness, their transition temperature, T_c, ranges from 4.4K to as least as low as 0.5K. A figure of merit of 50K^–1 is easily achieved. The films are mechanically extremely strong, and at room temperature show minimal aging. Using a simple heat treatment technique, T_c can be tuned to the desired operating range.     

薄膜铂热电阻特性分析

薄膜铂电阻在温度测量领域应用广泛,使用数量巨大。在很多行业中,已取代了传统的线绕式铂电阻,但由于其原理未被充分掌握,以及特性未被深刻认识,在使用过程中,实际性能指标常常不理想,其高精度和高稳定性未得到充分发挥。为此对薄膜铂电阻工作原理、结构和加工工艺进行了介绍、针对不同于传统铂电阻的电阻温度变化规律、热响应时间和自热效应的特性进行分析,对在开展高精度温度测量应用时需注意的问题予以说明。     

关于标准电阻转换法检定热电阻不确定度的分析

不直接采用电阻测量仪检定热电阻,而是通过测量标准电阻电压间接测量电阻来检定热电阻,证明此方法电测设备引人的不确定度更小     

Pressure Effect on BDA-TTP Conductors

The pressure-induced conducting behavior of the charge-transfer salts (BDA-TTP)₂X [BDA-TTP = 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene; X = ClO₄·H₂O, ClO₄, BF₄·H₂O, BF₄, and I₃] has been investigated. With increasing pressure, the transition temperature to insulator observed in the ClO₄·H₂O, ClO₄, BF₄·H₂O, and BF₄ salts increases. On the other hand, the resistance of the I₃ salt as a function of temperature at 10.0 kbar shows a drop attributable to a superconducting transition with an onset at 4.5 K. The superconducting transition temperature (T_c) can reach 8.2 K by applying a pressure of 10.3 kbar, but gradually decreases with further increases in the pressure.