Effect of annealing treatment on the anti-pulverization and anti-corrosion properties of La0.67Mg0.33Ni2.5Co0.5 hydrogen storage alloy

The La0.67Mg0.33Ni2.5Co0.5 hydrogen storage alloy was prepared by the vacuum intermediate frequency induction furnace followed by annealing treatment. The pulverization degree of both the as-cast and annealed alloy powders after gaseous hydriding and dehydriding cycle was investigated and the discovery was that annealing treatment could hardly ameliorate their anti-pulverization ability. The element content of La, Mg, Ni and Co existing in electrolyte before and after the electrochemical cycles by using ICP-AES technology was also analyzed and it showed that a large amount of La and Mg were dissolved in the electrolyte, but the amount of dissolution for La and Mg significantly declined when the alloy was annealed. The XRD analysis revealed that all the alloys consisted of two main phases AB3 and AB2 and a residual phase AB5 while annealing treatment made the AB2 phase decrease slightly. Furthermore, the anti-corrosion abilities of various elements in different phases of the as-cast and annealed alloy samples were studied by analyzing the element(La, Mg, Ni, Co) change with the corrosion time in phases AB3 and AB2 by means of EDS. It turned out that the element of La was mainly corroded out from the phase AB2 while not easily from the phase AB3. However, the element of Mg was both easily corroded out from the phases AB2 and AB3, but the corrosion was more obvious in the phase AB3. Therefore, annealing improved the anti-corrosion performances of La and Mg in the phase AB2.     

临近既有线隧道开挖施工控制爆破分析

临近既有线隧道开挖爆破施工会对既有隧道结构产生不利影响,造成结构物的变形、开裂、渗漏水等。文章通过对临近既有线隧道开挖控制爆破施工技术的探讨,浅析爆破振速及主振动频率控制对既有线隧道的影响,在确保既有隧道结构安全稳定的前提下,获得更好的爆破效果及开挖进尺,为临近既有线隧道的爆破施工提供参考。     

国内工程技术公司首次技术总负责建设大型现代化冷轧宽带钢生产线——唐山丰南1450mm冷轧薄卷板工程介绍(酸轧机组篇)

酸洗轧机联合机组是全连轧的一个发展方向,本文介绍了国内工程技术公司首次技术总负责、工程总承包建设唐山丰南1450mm冷轧薄卷板工程酸洗轧机联合机组的情况。该工程的顺利投产,开创了国内公司自主集成建设大型冷轧生产线的新模式,对推动我国钢铁工业坚持走自主创新之路、技术装备水平升级和结构调整具有重大的意义。     

唐山丰南1450mm酸洗轧机联合机组

介绍了国内工程技术公司首次技术总负责、工程总承包建设的唐山丰南1450 mm酸洗轧机联合机组生产线的工艺流程、主要机械设备及参数、电气传动及自动化控制系统。投产以来,设备运行良好,控制精度高,产品质量优异,取得了很好的经济效益。