快速评定砂浆配方对钢筋腐蚀的影响

用电化学方法测定砂浆试件中钢筋的极化电阻，并测定了砂浆的孔隙率，结果发现:砂浆的孔隙率、孔径分布与钢筋极化电阻大小有良好的对应关系。电化学方法能可靠、快速测定砂浆配合比、添加剂对钢筋腐蚀速度的影响。     

符号运算在求解车辆传动系扭振中的应用

介绍符号运算方法在用拉普拉斯变换方法求解车辆传动系扭振过程中的作用．针对弹性联轴器的匹配计算，给出了具体求解实例．实践表明，与传统的纯数值计算方法相比，符号运算方法可以方便准确地处理车辆传动系统扭振分析中的非线性等复杂问题，具有推广应用价值．     

离子注入对Cr12MoV钢表面组织结构和力学性能的影响

研究了Ｃｒ１２ＭｏＶ钢离子注入层的显微组织特征及其对表面性能的影响。结果表明，离子注入使Ｃｒ１２ＭｏＶ钢的表面硬度和耐磨性能得到显著改善，且存在着一个最佳的注入剂量，约为３×１０＾１＾７Ｎ＾＋／ｃｍ＾２左右。离了注入在Ｃｒ１２ＭｏＶ钢表面层中形成了大量细小弥散的第二相粒子，并使α－Ｆｅ晶格发生严重畸变，从而引起材料表面强化。     

ZnO陶瓷材料的负阻特性

介绍了ＺｎＯ陶瓷的负阻特性，主要研究了ＭｎＯ２掺杂和Ｎｉ２Ｏ３掺杂对ＺｎＯ陶瓷负阻特性的影响。     

Recrystallization/precipitation behaviour in microalloyed steels

Microalloyed high-strength low-alloy (HSLA) steels contain additions of Nb, V, Ti, or in combination, in amounts of 0.01 to 0.1 weight percent to improve mechanical properties, which are strongly dependent on the thermomechanical interaction taking place in the course of rolling mill processes. The recrystallizatian of hat-twisted austenite has been investigated in a cylindrical specimen (f 6×50 mm) machined from hat rolled plates of 0,052 wt % Niobium microalloyed steel. Continuous and interrupted torsion test were carried out in the temperature range 1123 K to 1173 K after a solution treatment of 1.5 minutes at 1423 K and torque-twist data were analysed. The various methods were discussed for obtaining results from torsion tests. The effect of precipitation kinetics was appreciated by way of connection t_p/t_p(red), where t_p is the experimental measured time for the peak stress and t_p(red) is the newly defined reduced time. The softening ratio X and time t_0.05R for start of static recrystallization were established.

The correlation between precipitation and recrystallization is presented as a graphs for chosen requirements (temperature of austenitization, carbon and niobium content and strain rate). If temperature goes below 850°C, the restoration processes are hardly suppressed, both are limited by diffusion and Nb(CN) precipitation, which are extended dynamically in the range of strains rates 10⁻² to 1 s⁻¹.

In the present paper, an attempt is made to derive the PRTT diagram and to define all mathematical equations for describing recrystallization times t_0.05R, t_0.5R, t_0.95R and t_0.05P for the start of precipitation. In real metal forming processes such as the hot rolling of plates or strips the knowledge of these parameters and results is extremely important for the the correct microstructure and sheet quality to be obtained.     

方块电阻测试中的有限元理论

介绍了用有限元方法计算半导体方块电阻四探针测试中二维点电流势场的模型并且证明了其正确性。由于有限元方法对边界没有限制，该方法为方块电阻测试中精确确定边界修正系数，更重要的是为微样品测试结构确定提供直接明了的理论依据。     

High-efficiency finishing process for metal mold by large-area electron beam irradiation

A new finishing process for metal molds by large-area electron beam (EB) irradiation is proposed in this study. In the large-area EB irradiation equipment used here, an EB with high-energy density is irradiated without focusing the beam, and so the EB with a maximum diameter of 60 mm can be used for melting or evaporating metal surface instantly. Experimental results show that the surface roughness decreases from 6 μmRz to less than 1 μmRz in just a few minutes under proper machining conditions. The corrosion resistance of metal mold surface also could be greatly improved by large-area EB irradiation. Furthermore, the surface roughness of tilting surface close to 90° could be well improved. Therefore, large-area EB irradiation method has a possibility to become a high-efficiency finishing process for metal molds.     

聚苯胺锂基润滑脂载流润滑下的摩擦学性能

制备了导电聚苯胺锂基润滑脂（简称PANI脂）和铜基银镀层材料（简称银层材料）。采用摩擦磨损试验机考察在无载流、载流及边界润滑条件下，铜基体材料（简称铜基材料）和银层材料的摩擦磨损性能。采用X射线衍射（XRD）、扫描电子显微镜（SEM）和电子能谱（EDS）对银层材料晶相及其表面磨斑形貌进行表征。结果表明，载流条件下，PANI脂润滑试验时的银层材料不仅具有良好的减摩抗磨性能，而且导电能力更强，其优异的减摩和抗磨性能归功于摩擦表面的保护膜和电流热效应引起的表面软化双重作用。     

Effect of reliability of grounding of the shaft of a turboset on the operation of devices for control and protection of exciting circuits

Disturbance of the grounding of the shaft of a turboset or its absence for technical reasons can result in failure, misoperation, limitation of the operating zone, errors or limitation of the sensitivity of devices for control and protection of exciting circuits from single-point leakage, and electroerosion of elements of the turboset structure. Measures for increasing the reliability of the grounding of the shaft are discussed. __________ Translated from élektricheskie Stantsii, No. 3, March 2006, pp. 61–66.