AZ31镁合金初始动态再结晶的临界条件研究

为确定AZ31镁合金初始动态再结晶的临界条件或临界应变，通过在变形温度范围473～623K、应变速率范围0．001-1 s^-1条件下进行等温压缩试验，利用所得数据并采用单参数方法，建立起AZ31镁合金初始动态再结晶的临界条件，即临界应变（εc）与变形条件（引入温度补偿应变速率因子即Zener-Hollomon参数）的定量关系，并对不同应变下合金微观组织的演变规律进行了研究。     

A machine vision approach to seam tracking in real-time in PAW of large-diameter stainless steel tube

Manual monitoring and seam tracking through watching weld pool images in real-time, by naked eyes or by industrial TV, are experience-depended, subjective, labor intensive, and sometimes biased. So it is necessary to realize the automation of computer-aided seam tracking. A PAW (plasma arc welding) seam tracking system was developed, which senses the molten pool and the seam in one frame by a vision sensor, and then detects the seam deviation to adjust the work piece motion adaptively to the seam position sensed by vision sensor. A novel molten pool area image-processing algorithm based on machine vision was proposed. The algorithm processes each image at the speed of 20 frames/second in real-time to extract three feature variables to get the seam deviation. It is proved experimentally that the algorithm is very fast and effective. Issues related to the algorithm are also discussed.     

球磨对ZrO2（Y2O3）超细粉末性能的影响

以共沉淀法制备煅烧态ＺｒＯ２（Ｙ２Ｏ３）超细粉末为研究对象，研究了球磨对其物理和烧结性能的影响，结果表明，球磨虽可以有效地减小粉末的团聚尺寸，但对粉末一次颗粒尺寸的的影响不大，球磨可以显著增加团聚程度较严重的锻烧态粉末的比表面积，但对团聚程度较轻的粉末，其影响大：球磨还可显著减小粉末的晶粒尺寸，这与粉末在球磨过程中发生了相变有关。此外，对团聚较严重的粉末，球磨可改善其烧结性能，但对团聚程度较轻的粉     

稀盐酸中锰结核还原浸出溶液净化除铁

针对酸性氯化物中黄铁矿还原浸出锰结核的溶液成分特点，选择黄钠铁矾法进行了沉淀分离铁的研究。结果表明温度和晶种以及溶液ｐＨ值是影响铁矾沉淀的重要因素。在ｐＨ２．０左右，溶液温度高于９０℃，足量晶种加入的情形下，１５０ｍｉｎ后可将溶液中的铁含量降至０．１ｇ／Ｌ。沉矾过程的表观活化能为９４．６６ｋＪ／ｍｏｌ。黄铁矿氧化生成的硫酸根随铁一同沉淀，从而消除了ＳＯ２－４在氯化物体系中的积累。     

EFFECT OF STRENGTH ON CORROSION FATIGUE BEHAVIOUR OF LOW ALLOY STEELS IN ARTIFICIAL SEAWATER

本文应用断裂力学及电化学等方法,研究了通过不同回火温度处理具有不同强度水平的34CrNi3Mo和40CrNiMo钢在人造海水中的腐蚀疲劳(CF)和应力腐蚀开裂(SCC)行为。试验结果表明,钢的强度对CF和SCC行为有着强烈的作用。随着钢屈服强度σ_s的提高,钢在海水中的SCC敏感性增大,腐蚀疲劳裂纹扩展速率dα/dN剧增。低合金钢在海水环境中的CF行为与SCC行为密切相关,而在CF条件下可促进钢的SCC敏感性。     

数控小孔冲床网眼平板加工中的波浪纹缺陷成因分析及排除

文章就数控小孔冲床加工纺织烘干设备中帘子网眼平板产生波浪纹缺陷的原因,进行了全面、详细的理论分析.在排除机床、模具精度影响的基础上,针对压料机构运动误差产生的机理和不利影响,详细分析了网眼冲孔加工产生波浪纹缺陷的根本原因,提出了相应的改进措施,在实践中具有良好的实用效果.     

表面技术用新型加热与干燥设备

夜面涂装加热与干燥设备是近年来开发的节电新技术,可较传统热风炉或一般远红外炉节电15～40%,炉内上下温差3～8℃。文章提出用系统优化的原理和方法对乳白石英管低温辐射加热进行研究,设计中采用辐射密度分布法和部份功率控制法。     

Internally humidified polymer electrolyte fuel cells using water absorbing sponge

Polymer electrolyte fuel cell (PEFC) mounted with two strips of polyvinyl alcohol (PVA) sponge is presented and the effect of operating conditions on the cell performance is investigated. Mounting the sponge wicks is advantageous for the humidification of dry inlet air and for the removal of liquid water in the cell. It was found that dry inlet hydrogen could be internally humidified by water diffusion from the cathode to anode when operating in a counterflow mode. The results show that the relative humidity of the inlet gases could have little effect on the performance of the cell mounted with two sponge wicks under certain operating conditions. At a cell potential of 0.5 V, the current densities of the sponge-mounted PEFC operated with dry air are 5% and 31% higher than those of the conventional one without wicks operated with saturated and dry air, respectively. The molar percentage of water vapor to total water exiting the cathode (R_gas) is an important parameter to gauge the cell performance with dry gases. A very large R_gas may cause the membrane dehydration and subsequently a low cell performance.     

高掺量粉煤灰路面试验研究获得成功

据悉，“十一五”期间六盘水市的煤产量将达到4000万t／年，火电装机容量为1000万KW，粉煤灰排放量将逐步增到1000万t左右。为提高粉煤灰的综合利用率，拟将粉煤灰混凝土用于公路路面工程。     

电磁屏蔽涂料的发展现状及趋势

电子产品的日益普及使得电磁干扰成为一个突出问题,应用电磁屏蔽涂料是消除电磁干扰简单而有效的方法,本文介绍了电磁屏蔽涂料的组成、效能评价方法、技术思想、存在的问题以及发展趋势。复合型以及水性屏蔽涂料具有广阔的研发前景,高效能、宽频带、寿命长的电磁屏蔽涂料将会受到市场欢迎。