大型复杂高精度波导钎焊设备的研制：简介ZHS—132型真空钎焊炉

应军事电子装备，特别是军用雷达预研和生产的急需，电子工业部第二研究所近期研制的成功大型、复杂、高精度波导钎焊设备ＺＨＳ－１３２型真空钎焊炉。文中主要介绍了该设备的开发背景和对波导钎焊工艺的影响，该设备的设计构思、结构和技术特征，使用功能和效果，以及推广应用前景。     

碳纤维表面处理对铝电解用硼化钛阴极涂层性能的影响

硼化钛阴极涂层是铝电解用可润湿性阴极材料中的一种，具有优良的抗钠渗透性和对铝液润湿性，可以有效地延长铝电解槽寿命。碳纤维是硼化钛涂层材料的增强剂之一．对硼化钛阴极涂层的性能影响很大。本文研究了不同工艺的液相碳纤维表面氧化处理法对硼化钛阴极涂层抗拉强度和粘接强度的影响。采用PTIR检测碳纤维处理后表面含氧基团的变化，寻找影响硼化钛阴极涂层性能的原因，从而达到最有效地提高TiB2阴极涂层抗拉强度和粘接强度的目的。结果表明，采用工艺(1)(10％HNO3，80℃、恒温5min．超声波、5min)对碳纤维进行表面处理最合理，处理后碳纤维表面含氧基团的含量最高．用其制备硼化钛阴极涂层的抗拉强度、粘接强度最大。     

Continuous Separation of Inclusions from Aluminum Melt Flowing in a Circular Pipe using a High Frequency Magnetic Field

The continuous separation of inclusions from aluminum melt flowing in a circular pipe using a high frequency magneticfield was investigated both theoretically and experimentally The separation efficiency was calculated based on thetrajectory method and compared with experimental results. It is found that the separation efficiency is a functilnondimensional parameters t_i·d_p~2B_e~2/μ_fμ_eα~2 and α/δ.The effective way to improve the separation efficiency is to increasethe effective magnetic flux density and decrease the pipe radius. and the value of α/δ should be kept about 2 in orderto obtain the optimum separation efficiency.     

Recovery retardation in equal channel angular pressed Al–Zr alloy during friction stir welding

The effect of Zr on reduction of hardness and microstructure in an FS weld of equal channel angular-pressed Al alloy was investigated. Zr addition to Al suppressed dynamic recovery in the thermomechanically affected zone and enabled retention of the high hardness of the ECA-pressed material throughout the weld.     

时效和重新训练对Cu－Zn－Al合金组织与记忆性能的影响

用约束训练法对时效后的Ｃｕ－Ｚｎ－Ａｌ形状记忆合金进行了重新训练。结果表明，在未发生贝氏体转变的条件下，时效所导致的记忆衰减可以通过重新训练予以改善。透射电镜分析指出，重新训练后，发生了马氏体的再取向，因时效而导致的细条状、台阶状变体大部分消除，且变体间的结合方式变为自协作性良好的孪晶关系，从而改善了合金的记忆性能。     

激光粒度分析仪测定氢氧化铝细颗粒方法的探讨

针对马尔文2000型激光粒度分析仪在氢氧化铝分析中对25μm粒径以下细颗粒的分析不太敏感，难以满足氧化铝生产分解过程对粒度控制的要求，对试验样品采用一些非常规的特殊处理方法，以提高细小颗粒在处理过样品中所占的体积百分比；研究了不同的样品处理方式对分析结果的影响。试验结果表明，只有对洗涤、过滤后的湿样进行分析，才能对分解料浆样品中的细颗粒的粒度分布进行准确地分析，得到满足试验和生产过程控制精度的结果。     

Microstructural changes accompanying repair welding in 5xxx aluminium alloys and their effect on the mechanical properties

At the shipyards, the aluminium alloy 5083 is welded with a multi-pass sequence using the metal inert gas technique. If, while checking the weld integrity either after welding or during service, defects are detected in the vicinity of the weldment, repairs are usually employed to extend the service life.

The repair method involves removal of the upper passes, depending on the thickness and re-welding under the same conditions.

Purpose of this paper is to examine the microstructural changes accompanying repair welding, define their effect on properties of primary importance and set, if possible, an upper limit as far as the number of repairs is concerned.     

微波功率管壳用焊料浇铸模的设计与制造

介绍一种微波功率管壳用焊料的模具的设计、制造工艺、表面处理和测量方法。