Nb对灰铸铁高温抗拉强度和抗氧化性的影响  

Influence of Niobium on High-Temperature Strength and Oxidation Resistance of Gray Irons

作　　者：朱洪波[1] 闫永生[1] 孙小亮[1] 华勤[1] 翟启杰[1] 

机构地区：[1]上海大学材料科学与工程学院,上海200072

出　　处：《现代铸铁》2011年第2期49-51,共3页Modern Cast Iron

基　　金：上海大学研究生创新基金(No.SHUCX102233);中信-CBMM铌钢研究与开发基金(No.036)的支持

摘　　要：研究了高温条件下,w(Nb)量为0.037%和0.11%对灰铸铁抗拉性能和抗氧化性能的影响,试验结果表明:w(Nb)量为0.037%时,试样为脆性断裂;w(Nb)量为0.11%时,产生了韧性断裂,试样断口出现了韧窝。铸铁加Nb后,石墨和珠光体得到细化,与此同时,富Nb相镶嵌于基体上,有利于提高灰铸铁的抗拉强度;Nb使石墨细化的作用也使氧原子难以进入基体内部,阻止氧化反应,有利于提高灰铸铁的抗氧化性。The influence 0.037% and 0.11% of niobium on the tensile strength and oxidation resistance of gray irons under a high temperature condition was investigated.The test results showed that brittle breaking occurred with the specimen containing niobium of 0.037%,and ductile breaking occurred with the specimen containing niobium of 0.11%,and the fracture exhibited ductile dimple.Adding Nb into cast irons caused graphite and pearlite finer,and by the way,the Nb-rich phase embedded into the matrix that was beneficial to increase tensile strength of the gray irons.The effect of Nb making the graphite finer also caused difficulty for the oxygen atoms to enter the matrix that was beneficial to prevent the oxidation reaction and to enhance the oxidation resistance of the gray irons.

关 键 词：灰铸铁 NB 高温性能 抗拉强度 抗氧化性 

分 类 号：TG251[金属学及工艺—铸造]