Volume 0,Issue 6,1994 Table of Contents
1994(6).
Abstract:
To the problems in the tube eddy testing, some improved ways are given by using a three-point probe matching the eddy instrument model ET-204 with low field voltage, and selecting a phase having the optimum singnal-to-noise ratio with impedance plane technique.The testing results show that the method possesses a jamproof capability for distant testing with high sensitivity.
To the problems in the tube eddy testing, some improved ways are given by using a three-point probe matching the eddy instrument model ET-204 with low field voltage, and selecting a phase having the optimum singnal-to-noise ratio with impedance plane technique.The testing results show that the method possesses a jamproof capability for distant testing with high sensitivity.
1994(6).
Abstract:
采用透射电镜（ＴＥＭ）研究了Ｎｉ４７Ｔｉ４４Ｔａ９合金中马氏体和β－Ｔａ相的形貌及精细组织。结果表明，马氏体主要呈细板条状和群团状两种形貌，其亚结构为孪晶；β－Ｔａ相粒子呈椭球状分布于ＴｉＮｉ基体中，其内部存在大量位错和孪晶。
采用透射电镜（ＴＥＭ）研究了Ｎｉ４７Ｔｉ４４Ｔａ９合金中马氏体和β－Ｔａ相的形貌及精细组织。结果表明，马氏体主要呈细板条状和群团状两种形貌，其亚结构为孪晶；β－Ｔａ相粒子呈椭球状分布于ＴｉＮｉ基体中，其内部存在大量位错和孪晶。
1994(6).
Abstract:
在１７５℃下实验测得ＭｎＣｌ２在ＮａＡｌＣｌ４熔体中的溶解度为０．０８６±０．００６ｍｏｌ％。锰可以在阴极上与铝发生共电沉积，生成含锰量为８ａｔｏｍ％～１０ａｔｏｍ％的二元合金。铝锰共电沉积可以显著地加快电化学成核步骤，从而完全消除低电流密度下絮状沉积产物的生成，且对高电流密度下枝晶产物的生成也有抑制作用。
在１７５℃下实验测得ＭｎＣｌ２在ＮａＡｌＣｌ４熔体中的溶解度为０．０８６±０．００６ｍｏｌ％。锰可以在阴极上与铝发生共电沉积，生成含锰量为８ａｔｏｍ％～１０ａｔｏｍ％的二元合金。铝锰共电沉积可以显著地加快电化学成核步骤，从而完全消除低电流密度下絮状沉积产物的生成，且对高电流密度下枝晶产物的生成也有抑制作用。
1994(6):1-7.
Abstract:
So far, many methods have been tried and applied in the synthesis of Bi-based superconductor powders including conventional solid state reaction route, solution self propagating high-temperature synthesis, co-precipitation route, sol-gel process, freeze-drying,solvent evaporating technique and micro-emulsion based powder synthesis. In this paper, the principles, advantages and disadvantages of these methods, and their applications in Bi-based superconductor powder synthesis are discussed.
So far, many methods have been tried and applied in the synthesis of Bi-based superconductor powders including conventional solid state reaction route, solution self propagating high-temperature synthesis, co-precipitation route, sol-gel process, freeze-drying,solvent evaporating technique and micro-emulsion based powder synthesis. In this paper, the principles, advantages and disadvantages of these methods, and their applications in Bi-based superconductor powder synthesis are discussed.
1994(6):8-12.
Abstract:
The method of production to prepare rare-earth hydrogen-stored alloys intended to be used for producing Ni-MH batteries is stated in brief. Multi-element rare-earth hydrogen-stored alloy ingots have been obtaineal by induction melting method of using ceramic crucible and water-cooling crucible, respectively. It is indicated that the concentration of impurity carried into the melt can be limited within some hundreds of ppm. By using a suitable water-cooling ceramic crucible, we can obtain the uncontaminated alloy ingots with homogenous and accurate composition. The process characteristics. of induction melting method with cold crucible and the result analysis of hydrogen stored alloy ingots obtained are introduced as well.
The method of production to prepare rare-earth hydrogen-stored alloys intended to be used for producing Ni-MH batteries is stated in brief. Multi-element rare-earth hydrogen-stored alloy ingots have been obtaineal by induction melting method of using ceramic crucible and water-cooling crucible, respectively. It is indicated that the concentration of impurity carried into the melt can be limited within some hundreds of ppm. By using a suitable water-cooling ceramic crucible, we can obtain the uncontaminated alloy ingots with homogenous and accurate composition. The process characteristics. of induction melting method with cold crucible and the result analysis of hydrogen stored alloy ingots obtained are introduced as well.
1994(6):13-23.
Abstract:
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
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
1994(6):28-31.
Abstract:
The novel yielding criterion for porous materials is employed to study the densification, workhardening and poisson's ratio of sintered materials during plastic processings. Relevant functions under uniaxial compressive stress stste are derived for the abobve factors the experimental data in literature are cited to test the predictions. Besides, recompressing process is also researched.
The novel yielding criterion for porous materials is employed to study the densification, workhardening and poisson's ratio of sintered materials during plastic processings. Relevant functions under uniaxial compressive stress stste are derived for the abobve factors the experimental data in literature are cited to test the predictions. Besides, recompressing process is also researched.
1994(6):36-40.
Abstract:
将颗粒形貌及粒度不同的２种仲钨酸铵（ＡＰＴ），按工业生产条件，进行掺杂钨丝生产的对比试验。结果发现：当ＡＰＴ的平均粒度为４０～４５μｍ，且具有多个晶块嵌镶成类球状的形貌特征时，可以进一步改善掺杂钨丝的综合性能。
将颗粒形貌及粒度不同的２种仲钨酸铵（ＡＰＴ），按工业生产条件，进行掺杂钨丝生产的对比试验。结果发现：当ＡＰＴ的平均粒度为４０～４５μｍ，且具有多个晶块嵌镶成类球状的形貌特征时，可以进一步改善掺杂钨丝的综合性能。
1994(6):41-44.
Abstract:
The crevice corrosion resistance of corn m ercially pure titanium and Ti-0.3% Mo 0.8% Ni alloy in boiling 25% NaCl and HCl solution was studied with electrochemical techniques. The results indicated that the Ti-0.3% Mo-0.8% Ni alloy have much better crevice corrosion resistance than commercially pure titanium. It is mainly related with the low hydrogen overpotential of the nickel which promoted the cathode polarization, increased the passivation ability. The nickel enriched in the internal crevice surface enhanced. the stability of passive film.
The crevice corrosion resistance of corn m ercially pure titanium and Ti-0.3% Mo 0.8% Ni alloy in boiling 25% NaCl and HCl solution was studied with electrochemical techniques. The results indicated that the Ti-0.3% Mo-0.8% Ni alloy have much better crevice corrosion resistance than commercially pure titanium. It is mainly related with the low hydrogen overpotential of the nickel which promoted the cathode polarization, increased the passivation ability. The nickel enriched in the internal crevice surface enhanced. the stability of passive film.
1994(6):46-51.
Abstract:
研究了在钼中掺入少量稀土元素钛的氧化物（Ｎｄ２Ｏ３）后，对钼丝的组织及性能的影响。结果表明，Ｎｄ２Ｏ３的加入明显细化了烧结钼坯条的晶粒；钼丝的再结晶温度和强度均随掺入Ｎｄ２Ｏ３量的增加而显著升高，并有较长的一次再结晶温区，经１７５０℃高温退火后，室温延伸率仍可达到３０％。实验表明，掺入Ｎｄ２Ｏ３量控制在１．０ｗｔ％左右时，加工钼丝材的显微组织和性能最好。
研究了在钼中掺入少量稀土元素钛的氧化物（Ｎｄ２Ｏ３）后，对钼丝的组织及性能的影响。结果表明，Ｎｄ２Ｏ３的加入明显细化了烧结钼坯条的晶粒；钼丝的再结晶温度和强度均随掺入Ｎｄ２Ｏ３量的增加而显著升高，并有较长的一次再结晶温区，经１７５０℃高温退火后，室温延伸率仍可达到３０％。实验表明，掺入Ｎｄ２Ｏ３量控制在１．０ｗｔ％左右时，加工钼丝材的显微组织和性能最好。
1994(6):52-55.
Abstract:
利用直接光谱法测定锑中Ａｓ、Ｃｏ、Ｂｉ、Ｐｂ、Ｃｒ、Ｓｎ、Ｍｇ、Ｆｅ、Ａｌ、Ｎｉ、Ｃｄ、Ｃｕ、Ｚｎ、Ａｇ等微量杂质，选择石墨粉作为缓冲剂，改善了谱线的重复性，对样品处理进行了详细的分析研究，以最佳的光谱测定条件，使元素测定下限达到３×１０－４％─３×１０－３％，相对误差在２２％以内，为金属锑纯度的全面分析建立了可靠的分析方法。
利用直接光谱法测定锑中Ａｓ、Ｃｏ、Ｂｉ、Ｐｂ、Ｃｒ、Ｓｎ、Ｍｇ、Ｆｅ、Ａｌ、Ｎｉ、Ｃｄ、Ｃｕ、Ｚｎ、Ａｇ等微量杂质，选择石墨粉作为缓冲剂，改善了谱线的重复性，对样品处理进行了详细的分析研究，以最佳的光谱测定条件，使元素测定下限达到３×１０－４％─３×１０－３％，相对误差在２２％以内，为金属锑纯度的全面分析建立了可靠的分析方法。
1994(6):56-58.
Abstract:
After investisating the effect of using monochromaton and filter on the measurement precision, a critical formula of optimal conditions for using monochromator was derived. At last, a practical operation method was proposed.
After investisating the effect of using monochromaton and filter on the measurement precision, a critical formula of optimal conditions for using monochromator was derived. At last, a practical operation method was proposed.
1994(6):65-69.
Abstract:
介绍了形状记忆合金热机械稳定性测试仪研制中的有关问题。包括环境温度、应力大小、响应时间和功率的确定以及整机的硬件、软件系统。该装置的冷热循环温度范围：－１５０℃～＋１２０℃，形变次数计算范围１～９９９９，最大载荷２０ｋｇ，最大位移５０ｍｍ，位移测量精度为±０．１ｍｍ。用该仪器记录的曲线可用来研究合金记忆性能的变化、临界负荷及使用寿命等评价记忆合金特性的实用参数。
介绍了形状记忆合金热机械稳定性测试仪研制中的有关问题。包括环境温度、应力大小、响应时间和功率的确定以及整机的硬件、软件系统。该装置的冷热循环温度范围：－１５０℃～＋１２０℃，形变次数计算范围１～９９９９，最大载荷２０ｋｇ，最大位移５０ｍｍ，位移测量精度为±０．１ｍｍ。用该仪器记录的曲线可用来研究合金记忆性能的变化、临界负荷及使用寿命等评价记忆合金特性的实用参数。
1994(6):70-73.
Abstract:
The development and features of cold hearth melting methods with electron beam and plasma are summarized, the furnace structure, operation principle and individual advantage of melting pure Ti and Ti-6Al-4V alloy are also stated in this paper.
The development and features of cold hearth melting methods with electron beam and plasma are summarized, the furnace structure, operation principle and individual advantage of melting pure Ti and Ti-6Al-4V alloy are also stated in this paper.
