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71.
降低制气炉外壁温度的有效措施 总被引:1,自引:1,他引:0
对引起间歇循环制气系统中制气炉改质室炉壁温度过高的原因进行了分析,对耐火砖结构、热电偶测温孔及人孔等处分别进行了改造,改造后3台改质室外壁温度平均降至100℃。 相似文献
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A. Schneuwly P. Gröning L. Schlapbach G. Müller 《Journal of Electronic Materials》1998,27(11):1254-1261
To reduce cost and enhance reliability for microelectronics applications, a complete understanding of the thermosonic bonding
process is required. In particular, the question of whether melting, diffusion, or significant heating occurs along the interface
during friction has often been raised. We present results obtained with a new device based on thermoelectric temperature measurements
to determine the temperature at the bond interface. In addition to the temperature information, the data characterizes the
bonding process in real time on a micrometer scale. The basic principle of the developed apparatus is temperature measurement
by an Au-Ni thermocouple fixed within the inside chamfer of a bonding capillary. Different bond substrates with high and low
bond contact quality have been investigated. The thermoelectric temperature measurements very precisely determines the bonding
behavior of the bond pads. A few nanometers surface contamination on a bond pad significantly reduces the temperature rise
at the bond interface and therefore impairs bondability of the substrate. These results demonstrate the sensitivity and accuracy
of the measurement principle. The apparatus is a powerful tool to measure the tribology of the bond system and to characterize
the bondability of different bond pads. 相似文献
74.
Here we describe a new mechanism of heat transfer between two solids separated by a distance. This mechanism does not involve the ambient air or adsorbed vapour films, and is therefore expected to remain active under perfect vacuum conditions. As will be described in detail, thermal charge fluctuations of one solid substrate kept at finite temperatures create an electromagnetic field—at infrared frequencies and of a short coherence length—which extends across the gap and effectively transports heat to the other solid. In our view this mechanism is responsible for the effective heat transfer observed recently by C. C. Williams and H. K. Wickramasinghe between a heated tip and a substrate. 相似文献
75.
本文用热电偶误差计算的通用方法(极限误差表达法)分析了构成快速钨铼热电偶测温误差的因素,从量的角度探讨了各因素对总的误差的影响,对如何认识快速钨铼热电偶的测温精度,提出了可供参考的观点。 相似文献
76.
An experimental system has been designed and constructed to investigate the drying rate, temperature and moisture profiles developed within food materials during forced convective air drying. The moisture profile was determined by employing the technique of gamma ray densitometry, and embedded thermocouples were used to sense temperature at different locations. The overall drying rate was measured using an electronic balance. A microcomputer and a computer front end were implemented for data acquisition and experimental control. Sample temperature and moisture profiles measured during drying are presented as a function of both drying time and the distance to the surface of the specimen. Both profiles described the drying phenomena inside the sample. The evaporation front was observed in a narrow region of the apple specimen, this front moved into the sample as drying progressed. The amount of apple shrinkage was determined to be linearly related to the distance which the evaporation front had recededfrom the initial surface. 相似文献
77.
介绍一种钢水连续测温新技术,该技术通过采用金属陶瓷外套管与双铂铑热电偶组成连续测温。热电偶,具有耐高温钢液熔蚀、抗热震、耐冲刷、不粘钢、精度高等良好性能,适用于连铸中间罐、VOD精炼炉中对钢液连续测温。 相似文献
78.
针对WC-Co涂层在磨削中磨削温度会引起相变,进而导致磨削缺陷的问题,以DMU70V数控铣床为平台进行WC-Co涂层磨削实验,利用K型热电偶和DGF40N光纤式红外测温仪测量磨削温度,借助x-射线衍射仪分析磨削前后WC-Co涂层物相组成.实验结果表明,利用热电偶测得的磨削温度与根据磨削过程中WC-Co涂层物质相变推测得到的磨削温度相差较大,利用WC-Co涂层物质相变推测的磨削最高温度与DGF40N光纤式红外测温仪测得的磨削最高温度一致,说明可以利用WC-Co涂层物质相变来推测磨削最高温度,为一些不能直接测量磨削温度的场合提供了新方法.WC晶粒在WC-Co涂层干磨削时大多异质生核,磨削后产生的WC晶粒粒度大,从而导致WC-Co涂层的强度下降,WC-Co涂层不宜干磨削. 相似文献
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