稀土Si_3N_4陶瓷材料中铝的络合滴定法测定

提出了强碱介质沉淀钇及有关杂质元素而与铝进行分离的方法。试液酸化后采用ＮａＦ析出法络合滴定测定铝。     

Electrochemical Investigation on the Formation of Dy-Fe Alloy in Molten Chlorides

ＥｌｅｃｔｒｏｃｈｅｍｉｃａｌＩｎｖｅｓｔｉｇａｔｉｏｎｏｎｔｈｅＦｏｒｍａｔｉｏｎｏｆＤｙＦｅＡｌｏｙｉｎＭｏｌｔｅｎＣｈｌｏｒｉｄｅｓＬｉｕＧｕａｎｋｕｎ（刘冠昆），ＴｏｎｇＹｅｘｉａｎｇ（童叶翔），ＨｏｎｇＨｕｉｃｈａｎ（洪惠婵），Ｙａｎｇ...     

塑料合金用反应型相容剂

反应型相容剂含有反应基团,可与含相应基团的聚合物起化学反应,因而在混炼过程中增容。本文系统地介绍各种反应型相容剂的设计、合成、品种和应用。     

GH871 合金的蠕变断裂机制

对采用AIM+ESR和VIM+ESR工艺冶炼的GH871合金在650 ℃的蠕变性能及特征的研究表明,与用AIM+ESR工艺冶炼的GH871合金相比,用VIM+ESR工艺冶炼的GH871合金在蠕变断裂过程中裂纹萌生的形式(包括裂纹形状及形成时间)和裂纹扩展至裂纹连接所需的时间均表现出明显韧化的特征.     

Surface Position-Resolved Thermophysical Properties for Metallic Alloys

Thermophysical properties are collective measures of a material to transport dynamical quantities of physical nature on its surface or through the bulk. As such, the exact nature of couplings between particles in a many-body assembly of building block atoms or molecules sensitively determines their values. The couplings between nearest neighbors are the product of the local elemental composition and the material phase. In this study, thermal cycling of a four-element Wood’s alloy specimen brings out cadmium-rich patches to the top surface of the specimen. An assembly of such patches leads to depth-dependent deviations of elemental composition from that of the bulk. Surface-layer atoms are driven to form a high temperature laser-produced plasma (LPP), and time-resolved spectroscopy of their emissions show the variability of elemental composition over surface positions as well as over depth from the surface. These thermal history-driven composition anomalies contribute to significant variability in the measured values of spectral emissivity and thermal diffusivity.     

电动机笼形转子铸铝常见质量问题分析

在电机制造中，笼形转子三相异步电动机的转子铸铝质量的好坏直接影响电机的性能及力能指标。因此本文对常见的转子铸铝质量问题进行了分析，并提出了相应地解决措施，以获得优质的电机。     

泡沫铝的动态压缩性能和吸能性研究

通过测量泡沫铝在动态和准静态压缩条件下的应力 -应变曲线 ,研究了泡沫铝的准静态和动态压缩行为以及不同应变条件下的吸能性 ,并对其应变率效应进行了分析。结果表明 ,在高应变速率和准静态压缩下 ,泡沫铝的σ -ε曲线均表现出弹性变形段、平缓段和密实段三阶段特征 ;泡沫铝的压缩性能具有明显的应变速率敏感性 ,随应变速率的提高 ,流动应力上升 ,吸能性升高     

镁合金表面喷铝防腐蚀层的微观组织分析

在AZ91D镁合金表面热喷铝，用以提高其表面的耐腐蚀性能。采用SEM，EPMA等方法对AZ91D表面喷铝扩散层的组织进行了仔细的观察与分析，发现在防腐蚀层上有大量的Mg17Al12相存在，且呈决状及非连续片状分布。经显微硬度测定，喷铝层硬度较镁合金基体高；腐蚀后这种相凸出于基体，比镁合金基体有较好的耐腐蚀性能。     

表面引发剂对熔融铝合金直接氧化生长的影响

为了控制熔融铝合金直接氧化法制备Al2O3/Al复合材料的氧化生长,采用ZnO,SiO2和MgO3种表面引发剂,研究它们对Al-Si-Zn合金氧化生长过程及Al2O3/Al复合材料组织形貌的影响.结果表明:与未使用引发剂时相比,使用SiO2,ZnO或MgO表面引发剂制备的粉末都能显著地缩短Al-Si-Zn合金的氧化生长孕育期,提高合金氧化生长速率,改善复合材料的胞状生长方式,提高复合材料的组织均匀度和致密度,为实际生产应用提供了依据.实验发现:ZnO表面引发剂的使用效果最为突出,其最佳添加量为12mg/cm2.     

Corrosion Behavior of a Sputtered K38G Nanocrystalline Coating with a Solid NaCl Deposit in Wet Oxygen at 600 to 700°C

A nanocrystalline coating of K38G alloy was obtained by means of magnetron sputtering. The corrosion behavior of cast K38G alloy and its sputtered nanocrystalline coating with a solid NaCl deposit in dry air or wet oxygen at 600 and 700°C have been studied and compared. The results indicated that the mass gain of the coating is higher than that of the cast alloy at 600 and 700°C. Therefore, nanocrystallization reduced the corrosion resistance at these temperatures. Furthermore, the mass gains of the coating and the cast alloy with a NaCl deposit in wet oxygen were less than that with a NaCl deposit in dry air. The relevant corrosion mechanisms are discussed.