着色法区分铁素体球墨铸铁中的渗碳体与铁素体  

Differentiation of cementite and ferrite in ferrite ductile cast iron samples with coloration etching method

作　　者：宗斌[1] 王二平[1] 魏建忠[1] 王国红[1] 

机构地区：[1]北京工业大学材料科学与工程学院,北京100124

出　　处：《金属热处理》2010年第2期96-98,共3页Heat Treatment of Metals

摘　　要：采用不同的侵蚀剂,进行了铁素体球墨铸铁中铁素体和游离态渗碳体的金相显示和区分试验。结果表明,采用常规腐蚀剂（2%~5%的硝酸酒精）,难以有效地分辨在铁素体球墨铸铁工件铸造过程中非常容易出现的游离态渗碳体,借助显微硬度也只能解决部分问题。在2%~5%的硝酸酒精预蚀后,采用碱性苦味酸钠溶液沸浸5~15 min,根据不同物相的着色效果,可以完美呈现铁素体球墨铸铁中的不同物相及成份偏析;也可以在样品预蚀后,采用苦味酸水溶液,同样根据着色效果的不同,实现快捷、有效的物相区分及评级。Different corrosive agents were used for metallurgical illustrative and differentiation experiment of ferrite and free cementite in ferrite ductile iron.The experiment results indicate that the usual application of traditional corrosive agents（2%~5% nitric acid alcohol）in metallurgical structure test is not effective in the recognition of free cementite that usually segregates in the foundry process of ferrite ductile iron workpiece,and the assistance of microhardness analysis could only solve part of the problem.To address this issue,5～15 min of boiling dip in alkaline sodium picrate solution after pre-erosion of 2%～5% nital can be adopted,thus the different phases and composition segregations in the ferrite ductile iron with high definition based on the pigmented effects of different phases;or solution of picric acid can be used after the pre-erosion,a similarly expedite and effective phase differentiation and gradation can be achieved also through different pigmented effects.

关 键 词：铁素体球墨铸铁 游离态渗碳体 硝酸酒精 碱性苦味酸钠溶液 苦味酸水溶液 着色法 物相区分 

分 类 号：TG115.211.3[金属学及工艺—物理冶金]