稀土镁球墨铸铁的起源及其早期发展——纪念稀土镁球墨铸铁投产40周年  

The Origin of RE-Mg Nodular Iron and Its Early Development--In Commemoration of 40-th Anniversary of RE-Mg Nodular Iron Putting into Production

作　　者：周亘 

机构地区：[1]中国第一汽车集团解放汽车有限公司无锡柴油机分公司,江苏无锡214026

出　　处：《现代铸铁》2005年第1期22-28,共7页Modern Cast Iron

摘　　要：上世纪60年代初,为了充分开发和应用我国丰富的稀土资源,包钢、锡柴、上海内研所和一机部系统的一些生产和科研单位曾各自或协同进行稀土球墨铸铁试验研究。结果发现稀土的球化作用较弱,稀土球铁的球化率不如镁球铁,但夹渣、缩松明显少于镁球铁。这种结果引起了用稀土和镁进行球化处理的设想,导致了稀土镁球铁的诞生,解决了当时国内球铁生产由于原材料和技术两方面原因引起的质量问题,对我国球墨铸铁的发展起了重要作用。研究表明,与镁球铁曲轴相比,稀土镁球铁曲轴的夹渣、缩松缺陷大幅度减少,疲劳性能和耐磨性能也明显提高,因而很快在全国范围内推广。在这之后,锡柴又试验成功稀土镁硅铁合金球化剂冲入球化处理法,取代比较不安全而且温降较大的压力包处理法,并将稀土镁球铁用于柴油机连杆、大断面曲轴以及重量达20t的16V300型气缸体,此外,1965年还研制成功等温淬火稀土镁球铁凸轮轴并投入大批量生产。稀土能中和微量元素及铁液中某些气体的反球化作用,而稀土使球墨畸变的作用也需要微量元素中和。稀土镁球铁发生石墨漂浮的临界碳当量是4.55%,与镁球铁基本相同。稀土在球铁中的应用要注意用量恰当,才能达到“扬长避短”,充分发挥其有利作用和免除其不利影响。In the early 1960 s, with the purpose to exploit and utilize the rich rare earth resource of their country, Chinese foundrymen, including the foundry technicians of Wuxi Diesel Engine Works (WDEW), had made efforts in research of rare earth nodular iron. As a result, it was found that the nodularizing effect of the rare earth is relatively weak, and the nodularity of the rare earth nodular iron is inferior to that of the magnesium nodular iron, however the former iron has obviously less dross and shrinkage than the latter iron. This result caused the attempt to use both the rare earth and magnesium as nodularizer to conduct nodularizing treatment that led to the birth of the rare earth magnesium nodular iron and solved the quality problems in nodular iron production at that time in China caused by reasons in both aspects of raw materials and technology, so it had played and is still playing a significant effect in nodular iron development of China. Investigation showed that, compared with magnesium nodular iron crankshafts, the RE-Mg nodular iron crankshafts have much less dross and shrinkage defects, and obviously higher fatigue strength and wear resistance. Therefore it was popularized quickly nationwide in China. Not long after that, it was again WDEW which had successfully developed the pour-over nodularizing treatment process ('sandwich' process) with RE-Mg-Si-Fe alloy as nodularizing agent to replace the before-used nodularizing process with the rare earth and magnesium being plunged into molten iron under pressure in a sealed ladle which was not very safe and caused severe temperature decrease, as well as further applied the RE-Mg nodular iron to connecting rods, heavy section crankshafts and heavy cylinder blocks with weight up to 20 t. In addition, in the beginning of 1965, WDEW also succeeded in development of the isothermally quenched RE Mg nodular iron camshafts and putthem into mass production. The rare earth can be used to neutralize the anti-nodularizing effect of some trace elements and some gass

关 键 词：稀土镁球铁 夹渣和缩松 球化与反球化 

分 类 号：TG143.5[一般工业技术—材料科学与工程] TG255[金属学及工艺—金属材料]