微量元素铋对厚断面球铁组织及性能的影响  

Effect of Bi on the Microstructure and Mechanical Properties of Heavy Section Ductile Cast Iron

作　　者：高文理[1] 岑鸽[1] 杨志超[1] 宋贤发 陈建军 

机构地区：[1]湖南大学材料科学与工程学院,湖南长沙410082 [2]宁波日月重工股份有限公司,浙江宁波315100

出　　处：《湖南大学学报（自然科学版）》2013年第6期74-79,共6页Journal of Hunan University:Natural Sciences

基　　金：宁波市重大(重点)科技攻关计划资助项目(2010B10014)

摘　　要：通过添加不同质量分数的微量Bi和调整残余稀土量,研究其对厚断面球铁组织、抗拉强度、伸长率、硬度和-40℃低温冲击韧度的影响.结果表明,对于180mm×180mm×200mm试块,添加0.012%Bi可以明显消除其碎块石墨;而对于250mm×250mm×300mm试块,加Bi只能在一定程度上抑制碎块石墨产生,随着Bi量的增加,其抑制作用呈先增强后减弱的趋势,加入Bi的质量分数最佳值为0.010%～0.012%,此时抗拉强度达337MPa,伸长率为10.4%,-40℃低温冲击功可达到10.5J.适当降低残余稀土量,调整wRE/wBi加=1.3～1.5,可以进一步抑制碎块石墨和改善综合力学性能.By adding different content of trace Bi and adjusting the content of residual rare earth,the effect on the microstructure,tensile strength,elongation,hardness and-40℃low temperature impact toughness was studied.The results showed that,for 180mm×180mm×200mm specimen,adding 0.012%Bi could obviously eliminate the chunky graphite.But for 250mm×250mm×300mm test block,adding trace Bi could only inhibit chunky graphite to a certain extent.With the increased amount of Bi,the inhibition of chunky graphite enhanced at first and then weakened,with the best value between 0.010%and 0.012%.Meanwhile,the value of tensile strength,elongation and-40℃low temperature impact toughness was 337MPa,10.4%and 10.5J,respectively.Reducing the content of RE and making wRE/wBiadd=1.3～1.5could further reduce the chunky graphite and improve the comprehensive mechanical properties.

关 键 词：球墨铸铁 铋 微观组织 力学性能 

分 类 号：TG255[金属学及工艺—铸造]