Development of ultra light magnesium-lithium alloys

Magnesium-lithium alloys are among the lowest density metallic materials. Addition of lithium, with a relative density of 0·53, in magnesium reduces the density of the alloy significantly. Furthermore, addition of nearly 11 wt.% lithium converts hexagonal close packed structure of pure magnesium to a body centered cubic lattice, markedly improving formability of the alloy. The development of these alloys, however, had been hampered due to the high reactivity of lithium and magnesium in the molten state and also, due to poor creep resistance and instability of mechanical properties at room temperature. In an attempt to indigenize these ultra light alloys for possible applications in Indian satellite programme, detailed research work was initiated in DMRL. The difficulties associated with producing sound cast ingots have been overcome by controlling melting and casting parameters of these alloys. Extensive work has been done on structure-property correlation of alloys with varying lithium content and minor alloying additions. Based on these work, advanced magnesium-lithium alloys have been developed with improved tensile properties, room temperature stability and creep resistance. Wrought products (plates/sheets) of magnesium-lithium alloy have been supplied to ISAC, Bangalore and are being used in their INSAT-2 programme. This paper describes the systematic studies carried out in the laboratory to indigenize these ultra light alloys.     

攀钢转炉炼钢用碳化硅提温的试验研究

低品位碳化硅是转炉炼钢的有效提高温剂。工业性试验结果表明，碳化硅加入８．０ｋｇ／ｔ钢水提温４０．３－７０．３℃（平均４８．４℃）；渣中ＴＦｅ降低１．３％；加提温剂有利于转炉内造渣脱硫和碱少炉渣对耐火砖的侵蚀。文中还给出了攀钢转炉半钢冶炼铸用钢不水时加与不加碳化硅的ｔλ，［Ｃ］λ区域。     

提高连铸浊环水水质浅析

介绍了太钢板坯连铸水处理系统的工艺流程，分析了连铸浊环水水质存在的问题。通过对冷却塔部分、铁皮坑、水泵调速等改造，以及选用新的水质稳定剂，使水质明显好转。     

圆筒形铸件缩松缩孔的产生原因及解决方法

针对圆筒形铸铁辊体冒口端面产生的缩松、缩孔缺陷，进行了举例说明、系统分析，找到了缺陷产生的原因及影响因素。通过解决措施的应用与实施，有效地克服了圆筒形辊体铸件冒口端面产生的缩松、缩孔缺陷，同时应用到其它大型圆筒形铸件中，都得到了良好效果。     

唐钢薄板坯连铸连轧生产中半无头轧制技术分析

介绍了热轧薄带钢生产中半无头轧制的优点，并对唐钢薄板坯连铸连轧生产中半无头轧制的工艺方案和关键技术进行了技术分析。     

铸造湿型小件缺陷产生的原因与控制

通过对铸造湿型小件产品缺陷典型实例的原因分析，从型砂的选择及配制、造型工艺、浇注工艺等方面提出控制缺陷产生的工艺方法。     

武钢第二炼钢厂连铸坯喷号机自动控制系统

对武钢第二炼钢厂连铸坯喷号机自动化控制景统配置、网络通讯、伺服控制系统进行了阐述；经运行考验证明系统性能提高、稳定可靠。     

论薄板坯连铸连轧产品质量优势

通过对薄板坯连铸连轧工艺的分析，深入研究了其产品的质量优势，同时还指出了在产品生产过程中需要重点注意解决的一些问题。     

连铸稀土加入工艺试验

对多流大方坯连铸机生产稀土钢的稀土加入工艺进行了试验,分析了钢包、中间包、结晶器喂稀土丝的优缺点,并进行了对比。根据包钢大方坯连铸工艺的特点和实际情况,选出了大方坯连铸稀土钢的稀土加入工艺。     

基于ANSYS的铸嘴流体耦合场三维有限元仿真分析

作者用大型有限元分析软件ANSYS对铸嘴内稳态层流铝熔体进行仿真分析。实现了三维建模。解决了三维热一流耦合求解的问题，得到铝流体的速度、压力及温度的分布图。分析了铸嘴出口速度和温度的分布规律及其对连续铸轧的影响。