陶瓷量块的比较测量分析

本文介绍了陶瓷量块的主要特性，指出陶瓷量块与金属量块在计量和使用上的不同点，分析计量检定中的常见问题并进一步探讨处理办法。     

关于陶瓷量块检定探讨

陶瓷量块与钢制量块材质不同，生产工艺也有很大的区别，因此在检定陶瓷量块时有许多不同之处，下面对用钢制量块作为标准量块检定陶瓷量块的结果进行不确定度分析。     

量块艾利点支承架装卡不适对量块测量的影响

本文阐述了量块检定过程中，量块在艾利点支承架上装卡不适对量块变动量的检定结果造成的影响。通过试验和分析，确定了主要的影响因素。并提出了使用艾利点支承架的注意事项。对量块变动量的检定有一定的参考价值。     

陶瓷量块及其检测方法

1陶瓷量块量块的制造、使用、检定、保养、精度等都会影响到用其作测量标准的机械零件、计量器具等精确度，因此，对量块的制造、检定、精度、使用等均有一定的要求。用GCrls轴承钢及硬质合金钢等金属制造的量块使用较为普遍，其制造及使用的情况也较为成熟，它具有金属材料的特性，性能稳定，加工方便，价格低廉，应用广泛。而用新型陶瓷材料制作的陶瓷量块却鲜为人知。制作陶瓷量块的陶瓷材料是氧化铝（ZrO。）陶瓷，氧化诸瓷的密度大、硬度较高，尤其是机械性能即抗弯强度和断裂韧性较高，具备了制造高精度量块材料的基本特性，可以保…     

以1000mm量块为例剖析大尺寸量块检定

量块的尺寸越大,受温度的影响也越大,其次是量块的尺寸越大,其侧面的平面度及平行度误差就越大,所以在检定时要考虑这些因素。一、量块检定测量方法：依据JJG146-2011《量块检定规程》进行测量。测量环境：温度为（20±0.3）℃;相对湿度为≤60%。假定被测对象是4等1000mm量块,那么标准量块就应该选3等1000mm量块。     

陶瓷量块组合测量及不确定度分析

１　引言我们知道陶瓷量块具有耐热、耐磨、耐腐蚀及质轻等特点,是继金属材料之后的新一代新型材料。由于陶瓷量块的线膨胀系数很接近钢量块,而它的弹性模数又和钢量块相同,所以我们认为陶瓷量块值得探讨,希望在探索中寻求较为完善的测量方法。大家知道量块只有一个可供使用的中心长度,如果把不同尺寸的量块相互研合在一起将使单值量块变为多值。而对于陶瓷量块是否能够研合使用,而组合后的尺寸是否能够满足和保证它的测量精度,就此而言,我们对陶瓷量块的组合使用进行了实验。２　研合过程及研合体实验我们对陶瓷量块１１２块组里的…     

如何确定量块检定周的长短

研究量块检定周期的长短问题，其首要的任务就是要在保持量块长度准确度用量少检定工作频繁度之间找到一个最佳交叉点。本通过几个典型案例分析来说明确定量块检定周期的长短的原则。     

大量程位移传感器用于三等量块检定时不确定度分析

对于三等或三等以下量块的检定，受位移传感器测量范围的精度的限制，一直采用比较测量方法。近年来，随着高精度大量程位移传感器的出现，使得采用直接测量方法检定量块成为可能。本文介绍了用大量程位移传感器直接测量量块的方法，并对其不确定度进行了详细分析。     

量块线膨胀系数测量装置的研制

本文叙述了采用比较法量块线膨胀系数测量装置的测量原理,量块线膨胀系数测量装置组成,装置各系统的作用和功能,量块线膨胀系数测量装置测量不确定度分析与评定等。通过分析和比对试验,证明了装置稳定可靠,满足JJG146-2011量块检定规程要求,实现了比较法测量量块线膨胀系数的目标。     

新疆与辽、吉、黑三省所量块量值的比对

1997年5月,国家局计量司对全国省级法定计量检定机构进行了考核。笔者作为赴东北考评组成员及盲样数据提供者,对辽宁、吉林及黑龙江省所的量块及其它计量器具的量值传递进行了考核,得出了本文所列举的量块量传数据及结论。一、比对的有关情况1．比对依据JJG146－1994量块检定规程;2．盲样量块由主持考核人单位新疆区所提供,为上海机床厂生产的编号为24217号的38套组量块,每省所抽取10块,抽取方法本着在各尺寸段均匀抽取的原则,要求各省所均检定为4等;3．各所使用的标准量块均为中国计量科学研究院在不同时间传递的有效期内的二等…     

高温ITO薄膜应变计制备及压阻性能EI北大核心CSCD

高温薄膜应变计被广泛应用于极端条件热端构件的应变测量。ITO薄膜应变计通常能够应用于1000℃以上的应变测量,为了研究ITO薄膜的显微结构、XPS光谱、阻温特性及压阻响应,采用磁控溅射在陶瓷基底上制备了ITO薄膜应变计,并在高温纯N2中热处理ITO薄膜。结果表明,其电阻温度系数稳定在-750×10-6℃-1,在1200℃下测试其应变特性,测得电阻漂移率为0.0018 h-1,应变因子为16。ITO薄膜在高温下具有稳定的电阻温度系数和低漂移率,为高温端部件应变的测量提供了可能。     

Local stiffening effect of 'double deck' bending strain gauges: part 1

In stress measurement where it is difficult or impossible to access the inside surface of the structure, "double deck" (DD) or "sandwich" bending strain gauges can be used to measure both the membrane and bending strains. A DD gauge consists of a pair of constituent foil gauges which are bonded on the upper and lower surfaces of a plastic base or filling. It is mounted on the external surface of the test specimen to measure the external surface strain, and by extrapolation, the internal surface strain of the specimen. The sensitivity of the DD bending gauge increases when the separation between the pair of constituent foil gauges increases. However, this also increases the stiffness of the whole gauge. If the stiffness of the DD gauge is significant compared with that of the plate to which it is attached, the presence of the gauge may cause significant changes in local stiffness and result in errors of strain interpretation. This study is presented in two papers. Part I presents an approximate, analytical solution for the local stiffening effect of a DD gauge and quantifies the errors in the strain measurement. Part 2, to appear subsequently in Strain, will present the verification of the solution using a three dimensional finite element calculation, a parametric study and a correction method that can be applied easily. The extrapolation errors due to the stiffening effect and random reading noises are also explored.     

Local stiffening effect of 'double deck1 bending strain gauges: part 2

In stress measurement where it is difficult or impossible to access the inside surface of the structure, "double deck" (DD) or "sandwich" bending strain gauges can be used to measure both the membrane and bending strains. A DD gauge consists of a pair of constituent foil gauges which are bonded on the upper and lower surfaces of a plastic base or filling. It is mounted on the external surface of the test specimen to measure the external surface strain, and by extrapolation, the internal surface strain of the. specimen. The. sensitivity of the DD bending gauge increases when the separation between the pair of constituent foil gauges increases. However, this also increases the stiffness of the whole gauge. If the stiffness of the DD gauge is significant compared with that of the plate to which it is attached, the presence of the gauge may cause significant changes in local stiffness and result in errors of strain interpretation. This study is presented in two papers. Part I, appeared in the Feburary 1996 issue of Strain, presented an approximate analytical solution for the local stiffening effect of a DD gauge, and quantifies the errors in the strain measurement. Part 2 (this paper) presents the verification of the. solution using a three-dimensional finite element calculation, a parametric study and a correction method that can be applied easily. The extrapolation errors due to the stiffening effect and random reading noises are also explored. The figure and equation numbers in this part are continuedfrom Part 1, but the reference numbering is specific to Part 2.     

浅谈精密压力表计量检定中应注意的问题

弹性元件式精密压力表广泛应用于生产领域的各行各业。计量检定是确保精密压力表量值准确的重要手段。但在检定前、检定时和检定结果处理的过程中仍有一些问题需要特别关注和注意,否则可能造成检定结果误判。     

Effects of externally-generated electrons on pressure measurements of inverted magnetron gauges at Diamond

Diamond Light Source (Diamond) utilises a large number of Inverted Magnetron Gauges (IMGs) for both monitoring the vacuum and as a source of interlocks for protection of the machine. During storage ring operation it has been found that, in the presence of the stored electron beam, charged particles, assumed to be electrons, impinging on some of the gauges cause the pressures indicated by the gauges to drop to zero which causes problems with the operation of the storage ring. Diamond has designed and fitted a magnetic filter at the neck of each affected gauge port to eliminate this problem. This paper reports on and discusses experiments and proposed experiments with an electron flood gun and IMGs from two different manufacturers (MKS Instruments and Pfeiffer Vacuum) aimed at obtaining a better understanding of the effect. Externally-generated electrons from the flood gun can cause serious errors in the pressures indicated by the gauges; the error can be positive or negative depending on the gauge current-measuring circuit. Methods aimed at eliminating these spurious pressure readings, such as magnetic filters, bias voltages within the gauges and the use of earth meshes and baffles are also discussed.     

真空计的发展概况与趋势

真空计量器具被广泛应用于各科学实验领域,种类繁多,样式各异。真空计的微型化是其主要发展趋势。概述了真空计的发展历程,重点对近年来真空计的最新发展作了梳理,并提出了某些特殊环境下真空度测量方法的构想。     

基于LabVIEW机器视觉的压力表自动化检定装置设计

在LabVIEW机器视觉功能的基础上,利用IMAQ Vision/Vision Assistant的图像处理功能,结合虚拟仪器串口通讯理论,设计了一套集图像采集、机器视觉模拟量读取、决策判断及I/O控制于一体的压力表自动化检定装置。经实验证明该装置采用工业相机可以实现自动识别压力表所显示的压力值,识别误差小于表盘分度值的1/10,满足压力表计量要求,实现了包括压力表的快速可靠检定、报表自动生成与检定数据管理的全自动检定功能。     

图像识别在指示表检定中的应用

介绍了一种基于计算机图像识别技术实现的指示表全自动检定仪的设计方法，着重介绍了检定过程中的指针示值自动判读方法。该检定仪采用了高精度的光栅传感器与计算机技术相结合，利用了光栅测长原理测定指示表推杆的位移，采用CCD摄像头摄取表盘图象，经计算机进行图象识别及数据处理得到指针读数，从而免除了人工读数，大大提高了检定效率，可自动完成各类指示表的示值误差和回程误差的检定。详细论述了检定仪的组成原理、机械结构及仪表示值判读的软件算法，并通过实验对仪器检定结果的准确性进行了检验。     

一种基于应变测量的放入式电子测压器设计

目的：设计一种新型的放入式电子测压器。方法：直接利用测压器的外壳来作为应变式压力传感器，代替了压电式压力传感器，结果：给出了这种传感器的灵敏度和动态响应频率。结论：这种基于应变测量的放入式测压器具有结构紧凑，成本低的优点。     

Strain gauges for superconducting magnet testing

A survey of commercially available strain gauges potentially suitable for testing of superconducting magnets is presented. Strain measurement errors caused by magnetic fields and temperature changes are discussed. Previously unpublished data for the magnetic field induced error for weldable half-bridge strain gauges are given, along with the results of a test for the temperature dependence of the magnetorestistance of modified Karma alloy foil gauges in the liquid helium temperature range. Apparent strain-vs-temperature curves for the weldable half-bridge gauges and metal foil gauges are shown. Errors caused by magnetic fields are in general repeatable from gauge to gauge, whereas errors due to temperature effects exhibit considerable variation from gauge to gauge in a lot of nominally identical gauges.