磨削温度计算机检测系统

本文提出了采用单片机对磨削温度检测的工作原理及软硬件的设计方法,具有测量精度高、直接显示等优点。当磨削温度超过允许值时,系统能开启红灯对操作者提出警告。文中还提出了一种新型的搭接式传感器的设计和制造方法,测量磨削温度时不必再进行烦琐的标定工作。     

浇注法制备表面复合材料用复合剂的强度表征及测试

用改进后的强度测试仪，检测分析了三种自制复合剂不同温度下的抗弯强度，探讨了复合剂强度的测试方法，结果表明：抗弯强度可用来表征用于浇注法制备金属基复合材料的复合剂强度，抗弯强度越高，铸件浇铸成型率越高。     

电弧喷涂铝青铜复合涂层的抗高温氧化作用与机理

采用铝青铜底层,外加厚度为0.1～0.2 mm的纯铝涂层可进一步地提高涂层体系的抗氧化性能.900 ℃加热12 h的10次循环氧化试验结果表明,纯铝层的应用有助于提高铝青铜涂层的自封孔能力,在涂层表面形成的增厚富铝氧化膜以及在涂层基体界面上形成的富铝氧化层都对钢铁基体的防护有利.复合涂层体系与试件基体结合可靠,没有早期失效迹象,是一种有希望的高温防护涂层体系.     

Ni含量对TiNi形状记忆合金相变行为的影响

用示差扫描热分析仪和光学显微镜系统研究了Ｎｉ含量对ＴｉＮｉ形状记忆合金Ｒ相和Ｍ相相变温度，相变热，热滞的影响。结果表明：在加热和冷却过程中，Ｔｉ－３３．３％Ｎｉ和Ｔｉ－７５．０％Ｎｉ不发生相变；ＴＭ，ΔＭ，ΔＨＭ和ΔＨＲ是Ｎｉ是含量的函数，ＴＲ和ΔＲ基本为一定值，与Ｎｉ含量有关。     

High-temperature oxidation of pure titanium in CO2 and Ar-10%CO2 atmospheres

The oxidation behavior of pure titanium has been investigated in the temperature range of 1000 K to 1300 K in CO₂ or Ar-10%CO₂. Optical microscopy, electron probe microanalyses, and X-ray measurements on the oxide scales formed during oxidation indicate that their structures are nearly independent of temperature and the corrosion atmosphere. The scales consisted of two layers, an external one and an internal one, having a rutile (TiO₂) structure. The parabolic rate law was confirmed for growth of the external scale and the permeation depth of oxygen in titanium with apparent activation energies of 266 and 226 kJ/mol, respectively. The rate-determining diffusion species in the oxidation processes are discussed.     

THERMOCOUPLE USED FOR TEMPERATURE MEASUREMENT OF ALUMINIUM CELLS BY DYNAMIC METHOD

ＴＨＥＲＭＯＣＯＵＰＬＥＵＳＥＤＦＯＲＴＥＭＰＥＲＡＴＵＲＥＭＥＡＳＵＲＥＭＥＮＴＯＦＡＬＵＭＩＮＩＵＭＣＥＬＬＳＢＹＤＹＮＡＭＩＣＭＥＴＨＯＤ￥Ｙｕ，Ｘｕｅｂｉｎ（ＩｎｓｔｉｔｕｔｅｏｆＣｏｍｐｏｓｉｔｅＭａｔｅｒｉａｌ，ＪｉａｏＴｏｎｇＵｎｉｖｅ...     

基于PC机和80C196单片机的温度微机控制系统

文章介绍了由PC机和80C196单片机构成的热处理温度微机控制系统,并就集中温度数据采集方法、PC机和单片机的数据通信格式、单片机软硬件设计、双向晶闸管的触发电路等相关技术进行了分析,给出了串行通信中断接收及数据处理程序设计流程图.     

高炉铜冷却壁凝固过程数值模拟

在对铜冷却壁砂型 金属型复合铸造条件下的热态工况进行分析的基础上,利用有限元数值模拟的方法首次建立了铸型传热分析对称模型。在模型中对铸型传热系统中的对流、辐射、接触边界条件和凝固潜热进行了处理,利用有限元分析软件ANSYS,分析了紫铜冷却壁的温度场的变化。数值模拟的结果与实际生产相当吻合。     

High temperature oxidation mechanism of dilute copper aluminium alloys

Dilute copper-aluminium alloys were oxidized in air from 700 to 1000 °C. Two distinctive behaviours were observed: alloys with at least 3 wt% aluminium showed excellent oxidation resistance in the whole temperature range. Alloys with 2 wt% or less aluminium exhibited good oxidation resistance up to 800 °C; but as the temperature was further increased, the oxidation rate of these alloys increased and became comparable to that of pure copper. A kinetic model was developed to explain the oxidation behaviour and indirectly determine the amount of dissolved oxygen in the alloys tested. It was found that the oxygen dissolved in alloys with up to 2 wt% Al exceeded its solubility limit in copper, whereas the dissolved oxygen in alloys with higher aluminium contents was below the solubility limit. This difference may account for the significantly different oxidation resistance.     

Cr与B对镍基高温钎料在Cf/SiC陶瓷基复合材料上润湿性的影响

研究了Cr和B元素对镍基高温钎料在3D-Cf/SiC陶瓷基复合材料上的润湿性的影响.试验结果发现,在真空度小于10-3 Pa,工作温度1100 ℃,保温时间10 min条件下,当钎料中的Cr元素含量为15%,B元素含量为0.6%时,镍基钎料在Cf/SiC上的润湿角为10°,然而B元素含量增加到2.4%后,润湿角增大到62°,表明钎料中的元素B降低钎料在Cf/SiC上的润湿性.钎料中的活性元素Cr对润湿有重要影响.镍基钎料在Cf/SiC上的润湿过程属于反应润湿,润湿界面生成多种碳化物和硅化物.采用扫描电镜与能谱仪分析界面的微观结构与成分,通过X射线衍射仪检测界面产物.