云南滇池地区下寒武统磷块岩的稀土元素特征及其地球化学演化

该区下寒武统磷块岩可以划分为原生、风化和强风化三种类型矿石，其中的有用组分磷灰石在强烈风化矿石中富集稀土元素，而磷块岩本身的稀土元素特征则取决于其中的矿物组成和风化程度。研究磷灰石和磷块岩中稀土元素的地球化学行为，有重要的理论和现实意义。     

青钢6~#高炉炉役后期低耗长寿生产实践

通过加强原燃料管理,合理调整热制度和造渣制度,优化高炉上下部操作制度,提高冷却系统操作水平,加强管理等措施,青钢6#高炉冷却壁破损得到有效控制,优化了煤气流分布,实现了炉役后期的高效、低耗、稳定生产。     

Low cycle fatigue behavior of René 80 at elevated temperature

Low cycle fatigue of René 80 was studied at 871 and 982 °C. It was found that when the data were represented on the basis of plastic strain, the life increased with decreasing frequency and imposition of a 90 s hold at maximum strain. Transmission electron microscopy studies showed that the ′ coarsened and an interfacial array of edge dislocations developed. The density of dislocations in the matrix was very low. Light optical microscopy revealed that cracks generally inititiated at oxide spikes in surface connected grain boundaries. A crack initiation criterion based on the maximum stress and oxide depth at the time of crack initiation was found to represent the data very well. Based on that representation, an expression for the initiation fatigue life was developed. That expression includes temperature, frequency and cyclic stress strain parameters as variables. S. Liu, formerly Research Associate at the University of Cincinnati.     

低膨胀GH907合金700℃长期时效后的性能

研究了低膨胀GH907合金经700℃×1000小时长期时效后的组织和性能.结果表明GH907合金经700℃长期时效,强度有所降低,但仍保持在较高水平;持久性能稳定,无缺口敏感性;具有良好的综合性能.     

GH4720Li合金中温区低周疲劳行为研究

奥氏体沉淀强化GH4720Li合金用于制备航空发动机涡轮盘,其服役条件下的疲劳性能是当前研究的热点.研究了GH4720Li合金在中温区(450和550 ℃)不同应变条件下的低周疲劳行为.结果表明,GH4720Li合金的剪切模量和杨氏模量随着温度的升高而不断降低,但是中温区的抗拉强度和屈服强度不随温度而剧烈下降.GH47...     

Computer Simulation of Microstructure Evolution of 82B Rod at Different Cooling Rates

According to thermodynamics and kinetics of phase transformation,a mathematical model of phase transformation was proposed,and the microstructure evolution of an 82B rod at different cooling rates was simulated by using the FEM software Marc/Mentat,based on the measurement of time-temperature transformation（TTT）curves of the 82B rod.The simulated results were in good agreement with the actual measurements.From the results of computer simulation it was found that the cooling rate of the 82B rod,after laying,should be controlled within 5-8 ℃/s.In the microstructure of rod there were over 95% of pearlite volume fraction and a small quantity of dispersive martensite（less than 5%）.     

分时电流供电对长周期锌电积的影响研究

通过控制锌电积的电流密度按用电峰时段300A/m2、谷时段600A/m2及平时段480A/m2进行长周期锌电积试验,考察了分时供电对锌电积阴极锌质量、电流效率、直流电单耗及电费的影响,并与工业生产实际进行对比分析。结果表明,对于年产12万t锌锭的企业,锌电积生产每年节约电费约2 100万元。     

Low temperature strengthening in niobium-hydrogen single crystals

The mechanical behavior of high purity niobium and niobium-hydrogen single crystals at temperatures in the range 77° to 380°K was investigated. Thermally activated hardening by hydrogen in solution is appreciable at temperatures ≲150°K. However, hydride precipitation occurs at these temperatures, can be strain-induced during mechanical testing, and accounts for the largest part of the decrease in ductility in alloys with up to 720 at. ppm of hydrogen. The influence of hydrogen additions and the effects of purification on the low temperature flow stress of niobium demonstrate the large influence of interstitial solutes on the strength of bcc materials at low temperatures. Formerly Graduate Assistant, Division of Metallurgy and Materials Science, Case Western Reserve University, Cleveland, Ohio     

长结焦时间下焦炉管理的探讨

焦炉的结焦时间延长,导致焦炉的生产操作、炉温的控制、炉体维护、集气管压力等方面都要受到影响,本文从以上几个方面,结合我厂实际操作进行了分析。     

韶钢钢包系统长周期零事故控制技术

介绍韶钢第三炼钢厂钢包系统工艺技术的选用、改进和现场有效、可控管理的运用、推广,实现了钢包系统长周期零事故。     

转炉煤气风机长周期平稳运行方法探究

煤气风机是转炉炼钢生产线的核心设备,风机能否长周期平稳运行,对炼钢生产意义重大。文章介绍了一种新的方法,使转炉煤气风机长效平稳运行。