【作者】 刘明雪；

【导师】 刘赵铭；

【作者基本信息】 大连交通大学 ， 材料加工工程， 2008， 硕士

【摘要】 球墨铸铁自问世以来,不断受到各个国家和地区的重视,与铸钢件相比,具有生产工艺简单、成本低廉、耐磨性能优良等优点,因而在国民经济的各行各业中有着广泛的应用,而且逐渐成为重工业中最重要的部分。在球墨铸铁的生产过程中,球化处理是非常关键的技术,球化剂和球化工艺是其重要的组成部分。几十年来,国内外学者对球化剂及球化工艺方面进行了大量的研究,虽然已经取得了很多的研究成果,但在很多技术方面还有待于继续改进,尤其是在当今提倡可持续发展的社会环境下,对球化剂和球化工艺的要求越来越高。本文研制出一种新型球化剂——粉体球化剂,并且采用一种与之相适应的球化工艺进行球化处理,将其进行生产试验研究。制取粉体球化剂的工艺过程大致为:块状球化剂——机械破碎——机械化学研磨——粉体球化剂。球化工艺采用改进型冲入法,通过多次试验证明,这种球化工艺对粉体球化剂进行球化处理起到了至关重要的作用。本文首先对粉体球化剂的球化工艺进行了大量的研究,并进行大量现场试验;然后将采用粉体球化剂和块状球化剂生产出的球墨铸铁进行了显微组织和力学性能的对比分析,同时对粉体球化剂加入量的改变对球墨铸铁质量的影响进行了深入的研究,并得出了粉体球化剂的最佳加入量。结果表明:采用粉体球化剂进行球化处理,Mg-RE吸收率得到明显提高,与块状球化剂相比,加入量减少了30%,节省了生产成本,可以提升企业的市场竞争力;通过整个现场试验观察,采用粉体球化剂明显改善了铸造车间的工作环境,工人的身体健康得到了保障,具有显著的环保效应;同时,采用光学显微镜和力学性能测试等手段对两种球化剂生产出的球墨铸铁的组织与性能进行了研究和讨论,粉体球化剂与块状球化剂相比,生产出的球墨铸铁的显微组织有所改善、力学性能也有所提高。更多还原

【Abstract】 More and more attentions are paid to ductile iron by every country and region, since it came out. Comparing with steel castings, ductile iron has a lot of advantages, for example, simple production process, low cost and excellent wear-resistant. So it is widely used in every trade of national economy and gradually becomes the most important part in heavy industries.During the production process of ductile iron, nodularization treatment which is composed by nodularizing alloy and spherpidizing process is the key technology. Over the past decades, scholars at home and abroad do lots of researches on nodularizing alloy and pherpidizing process, and have obtained lots of research achievement. But they must go on improving the technologies, because the requirement of noduarizing alloy and spherodizing process is higher and higher, especially in present society environment of sustainable development.A new type of noduarizing alloy—nodulizer powders is developed, and the spheroidizing process suitable for it is used to nodularization treatment in this paper. The technological process of preparation nodulizer powders is as follow: bulk nodularizing alloy—direct separate—mechanical attrition treatment—nodulizer powders. The spheroidizing process applies improved pour-over nodularizing treating process. This spheroidizing process is proved to have an important effect for nodulizer powders to nodularizing treatment by multiple experiments.At first, lots of researches have been done about spheroidizing process of nodulizer powclers, and many times experiments have been carried out. Then contrasted and analyzed the ductile iron produced by nodulizer powders and the bulk nodularizing alloy in microstructure and mechanical properties. Meanwhile, deeply studied the effect of ductile iron quality by changing the adding quantity of nodulizer and obtained the best adding quantity of nodulizer powders.The experimental results indicate that the absorption rate of Mg-RE increases obviously when using nodulizer powders to nodularizing treatment. Comparing with bulk nodularizing alloy, the adding quantity of nodulizer powders decreases 30%, so the cost will be saved and the market competitiveness of manufacturing enterprises will be improved. By observing the whole on-line experiments, we can notice that: the working environment of foundry shop is improved, the flash and smoke decrease apparently, the protection of workers’health is getting better. So we can say it has a good environmental protection effect. When using optical microscope and mechanical behavior to research and discuss the tissue and natural capacity of ductile iron produced by two kinds of nodularizing alloy, the microstructure and mechanical behavior of ductile iron produced by the nodulizer powders are much better than that produced by bulk nodularizing alloy.更多还原