纯铁纯度对其再结晶织构及晶粒Schmid因子的影响  

Effect of purity on recrystallization texture and grain Schmid factor of pure iron

作　　者：高新强 彭伟 范增为 白佳鑫 韦习成[1] 董瀚[1] GAO Xin-qiang;PENG Wei;FAN Zeng-wei;BAI Jia-xin;WEI Xi-cheng;DONG Han(School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China;Hebei Longfengshan Casting Industry Co.,Ltd.,Wu'an 056300,Hebei,China)

机构地区：[1]上海大学材料科学与工程学院,上海200444 [2]河北龙凤山铸业有限公司,河北武安056300

出　　处：《钢铁》2022年第8期160-167,共8页Iron and Steel

基　　金：河北省重点研发计划资助项目(20311009D);上海市军民融合发展专项资金资助项目(2020-jmrh1-kj31)。

摘　　要：为了研究纯铁纯度对其再结晶织构及Schmid因子的影响,以商业的2N8、3N5纯铁和实验室制备的4N级公斤级高纯铁为原料,通过退火再结晶和EBSD研究了2N、3N、4N纯度纯铁再结晶织构特征和晶粒的Schmid因子。结果表明,2N8、3N5和4N3纯铁的晶粒组织均为等轴铁素体,残余应力少、位错密度低,样品再结晶完全。其中,2N8和3N5纯铁的织构呈现出相同的分散分布特征,而4N3高纯铁织构特征集中,随机织构较少。ODF图和取向线分布密度进一步表明,2N8和3N5纯铁具有相似的α织构{hkl}〈110〉和γ织构{111}〈uvw〉特征及变化趋势,即两者都在α取向线的{111}〈110〉取向具有较高的分布密度和γ取向线密度随φ的增大而有降低;而4N3高纯铁具有〈113〉||X和γ织构特征,且包含利于材料力学性能各向异性的{332}〈113〉织构,另外,其γ取向线密度随φ的增大逐渐升高,直至{111}〈112〉取向密度高于2N8和3N5纯铁。晶粒Schmid因子及其频率分布直方图结果表明,2N、3N、4N纯铁均存在低Schmid因子晶粒被高Schmid因子晶粒包围的现象,且在{110}〈111〉、{112}〈111〉和{123}〈111〉这3个滑移系下晶粒Schmid因子总和平均值为0.467(4N3)>0.461(3N5)>0.459(2N8),呈现出纯铁晶粒Schmid因子总和平均值随纯度增大的趋势;根据Schmid定律可知,4N3纯铁的织构特征最有利于其变形。综上所述,在本工作中,随着纯铁纯度由2N8提升至4N3,样品中杂质原子减少,促进了4N3高纯铁产生强烈的〈113〉||X和γ织构特征以及利于材料力学性能各向异性的{332}〈113〉织构,增大了其晶粒Schmid因子总和平均值。In order to study the effect of purity on recrystallization texture and Schmid factor of pure iron,the recrystallization texture and Schmid factor of 2N,3N,4N pure iron were studied by annealing recrystallization and EBSD with commercial 2N8 and 3N5 pure iron and 4N3 kg high purity iron prepared in laboratory.The results show that the grain structure of 2N8,3N5 and 4N3 pure iron is equiaxed ferrite with low residual stress and dislocation density,which was completed recrystallization.Among them,the texture of 2N8 and 3N5 pure iron showed the same dispersive distribution characteristics,while the texture of 4N3 high purity iron was concentrated with less random texture.The ODF figures and distribution density of orientation line further show that 2N8 and 3N5 pure iron have similarα{hkl}〈110〉andγ{111}〈uvw〉texture characteristics and variation trend that they both have higher distribution density in theαorientation{111}〈110〉and theγorientation line density decreases with the increase ofφ.However,4N3 high purity iron has〈113〉||X andγtexture,and contains{332}〈113〉texture which is favorable to anisotropy of mechanical properties.In addition,theγorientation linear density increases with the increase ofφuntil the orientation density of{111}〈112〉is higher than that of 2N8 and 3N5 pure iron.The results of grain Schmid factor and its frequency distribution histogram show that low Schmid factor grains are surrounded by high Schmid factor grains in 2N,3N,4N pure iron.In the three slip systems{110}〈111〉,{112}〈111〉and{123}〈111〉,the average of sum of Schmid factors of grains is 0.467(4N3)>0.461(3N5)>0.459(2N8),showing the trend of increasing with the increase of pure iron purity.According to Schmid′s law,the texture characteristics of 4N3 pure iron are most conducive to its deformation.In conclusion,as the purity of pure iron increases from 2N8 to 4N3,the impurity atoms of sample decrease,which promotes the formation of strong〈113〉||X andγtexture characteristics and{332}〈113�

关 键 词：高纯铁 EBSD 再结晶 织构 Schmid因子 

分 类 号：TG141[一般工业技术—材料科学与工程]