Sn-Cu系无铅钎料的研究现状与发展

介绍了无铅钎料应用时应该满足的基本要求和Sn-Cu系无铅钎料的国内外研究和应用现状,概述了Sn-Cu系无铅钎料润湿性能、物理性能、力学性能等方面的一些特点,分析探讨了Sn-Cu系无铅钎料存在的不足,详细阐述了添加不同合金元素(如Bi、Ag、Ni、RE等元素)对Sn-Cu系无铅钎料性能的影响规律,并对Sn-Cu系无铅钎料的应用前景和发展方向进行了展望.     

BP神经网络在液压试验台故障诊断中的应用

分析了BP神经网络的结构及算法，并对液压试验台的故障模式用BP神经网络来进行诊断，从而提出了一种新的解决液压试验台故障诊断的方法。     

高纯钛的反复弯曲疲劳

通过对不同应力幅度下高纯钛的反复弯曲疲劳的研究，发现在较低应力幅度下（～±１００ＭＰａ），材料表现出循环软化，伴随表面滑移带数量的增加、发达的滑移带挤出片的出现。疲劳裂纹萌生主要与滑移带相关，在挤出物内存在两类疲劳损伤形式：沿滑移带的孔洞和与滑移带垂直的微裂纹。在较高应力幅度下（～±２００ＭＰａ），则表现为硬化，次滑移及晶界附近多个滑移系同时起动，有大的形变孪晶出现。裂纹于滑移带、李晶界和晶界结点萌生。断口特征复杂，但与表面变形特征有对应关系。ＴＥＭ亚结构分析表明，随应力幅度的提高，位错组态分别为散乱分布于滑移面的偶极子、位错束带和位错胞。李晶内存在复杂的精细结构，而且有堆垛层错出现。     

稀燃车用催化剂的研究进展

稀燃车用催化剂是汽车尾气净化催化剂今后发展的方向，在稀燃条件下如何处理NOx是稀燃车用催化剂面临的巨大挑战。本文详细地评述了近年来国内外在这方面的研究工作，包括选择催化还原催化剂、存储还原催化剂和组合多功能催化剂的研究进展。     

高速切削机床中的磁轴承

高效化是机械制造的永恒主题之一。本文简介了高速切削的理论依据及其优点，分析了磁悬浮轴承的原理、特点以及磁浮轴承在高速切削机床上的应用情况，从而说明了磁浮轴是高速切削机床最理想的轴承之一。     

Thermodynamic assessment of the Fe-U binary system

The Fe-U system is one of the binaries of the U-Fe-Zr-O quaternary system that is important for a safe nuclear program. A new thermodynamic assessment of Fe-U is presented, taking into account some recent thermodynamic measurements: enthalpy of formation and of melting as well as heat capacities for both intermetallic compounds Fe₂U and FeU₆. The calculated phase diagram and thermodynamic data generally agree very well with the experimental values. The calculated temperature of the peritectic transformation [FeU₆ ↔ liquid + bcc-U] is equal to 1104 K, which is higher than in the previous assessments, but in agreement with Labroche’s value. However, the experimental melting enthalpy of FeU₆ is not reproduced by the present set of thermodynamic parameters.     

The Structure Stability of Carbide-Free Bainite Wheel Steel

Metallographic structures of carbide-free bainite steel wheel rim are mainly composed of supersaturated lath ferrite and retained austenite film among bainitic ferrite laths. It is suspected that supersaturated ferrite and retained austenite are likely to decompose under the influence of temperature change and mechanical stress. Stability of wheel rim structure is studied by means of x-ray diffraction, dye microscopy, and micro-hardness test. When the samples are tempered in the range of 150-350 °C, the retained austenite films are at the state of relative stability. Fifty percent of retained austenite is decomposed when the sample is tempered at 400 °C. Microhardness increases when the sample is tempered at 150 °C. The decrease in hardness is mild when the samples are tempered from 200 to 500 °C. The mechanical stability of retained austenite film is studied with tensile sample under the effect of tensile stress. The retained austenite appears to be stable in low and middle degree of deformation, and decomposition occurs at great amount of deformation. Diffraction peak of carbide is not found in all above experiments. The steel enriched silicon prevents the carbide precipitation during the transformation. It indicates the carbide-free bainite wheel steels have an excellent thermal and mechanical stability.     

我国人工皮革发展机遇的探讨

介绍了国外超细纤维人工皮革的产销与应用情况．追溯了国际上这一领域最新技术的进展．通过对国内未来几年市场需求的分析与预测，提出了应在高起点上发展我国人工皮革的思路。     

纳米Fe2O3的制备与气敏性质的研究

报道了纳米氧化铁的制备工艺，采用沉淀法、溶胶凝胶法制备了纳米α-Fe2O3、γ-Fe2O3粉体，用热重－差热分析（TG－DTA）、X射线衍射（XRD）、透射电镜（TEM）和二次粒度分布对粒子进行表征，并制作了气体敏感元件。讨论了纳米氧化铁的制备工艺对气敏性质的影响。     

邻氨基苯磺酸生产装置技术改造

通过改进生产工艺与设备,提高了装置生产能力和产品质量指标,达到了降本增效的目的。