Microscopic Characterization of Different Shrinkage Defects in Ductile Irons and their Relation with Composition and Inoculation Process
Microscopic Characterization of Different Shrinkage Defects in Ductile Irons and their Relation with Composition and Inoculation Process
复制标题
球墨铸铁不同缩松缺陷的微观表征及其与成分和孕育工艺的关系
DOI：
10.1007/s40962-016-0120-9
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发表时间：
2017
影响因子：
2.6
通讯作者：
N. Llorca
中科院分区：
文献类型：
--
作者：
A. Regordosa;N. Llorca
缩孔成为对球墨铸铁零件的生产产生负面影响的最重要的缺陷之一。对受影响部件进行的定期检查表明，根据熔体成分、布局以及文献中报道的许多其他加工变量，可以获得不同的收缩形态。然而，最大限度地减少这些缺陷需要更详细地了解它们的内部特征以及与产生最大影响的加工变量的关系。在本研究中，研究了熔体的碳当量含量、孕育和热特性，作为生产八个测试部件的变量，这些部件旨在促进收缩的形成。通过金相技术和 FE-SEM 分析了每种情况下获得的不同缺陷，并分析了它们的特征和尺寸与所选变量的相关性。已发现碳当量对收缩发生率的影响最强。对不同闭合缺陷的内表面中发现的特征进行了讨论，并且还描述了每种情况的可能解释。
Shrinkage becomes one of the most important defects that negatively affects the production of ductile cast iron parts. Regular inspections made on the affected parts show that different morphologies of shrinkage can be obtained according to the melt composition, to the layout and to a number of other processing variables that have been reported in the literature. However, minimization of these defects demands a more detailed understanding of their internal features and the relationship with the processing variables causing the greatest effect. In the present study, carbon equivalent content, inoculation and thermal characterization of melts have been studied as variables for producing eight test parts which have been designed for promoting the formation of shrinkage. The different defects obtained in each case have been analyzed by means of metallographic techniques and FE-SEM and their characteristics and size correlated with the selected variables. It has been found that carbon equivalent shows the strongest effect on shrinkage incidence. A discussion about the features found in the internal surfaces of the different closed defects is done, and possible explanations for each case are also described.