低氮低钒D36船板钢中析出相的特征及沉淀强化作用  

Characteristics and strengthening effect of precipitates in low-nitrogen and low-vanadium D36 ship plate steel

作　　者：李贞顺[1] 李胜利[1] 孙卫华[2] 徐洪庆[2] 

机构地区：[1]山东大学材料科学与工程学院,山东济南250063 [2]济南钢铁集团公司技术中心,山东济南250101

出　　处：《材料热处理学报》2012年第4期68-71,共4页Transactions of Materials and Heat Treatment

基　　金：2012年济南市高校自主创新项目

摘　　要：通过透射电镜观察了低氮低钒D36船板钢的析出相特征,并讨论了其沉淀强化作用。结果表明:实验用钢的组织均为铁素体-珠光体组织,珠光体中未见析出相,仅在铁素体中观察到析出相。VCx析出相为矩形片状形貌,在铁素体基体上均匀弥散沉淀,析出相以{100}α-Fe为惯习面,与基体存在Baker-Nutting取向关系;少量球状V6C5析出相(单斜结构)与铁素体基体存在一定取向关系,可能是共格VCx相通过碳原子重新分布转变而成。低氮低钒钢中加入0.05%V,沉淀强化值约为63 MPa,加入微量铌后在铁素体内形成一定密度的位错能有效发挥钒的沉淀强化作用。Characteristics of precipitates in low-nitrogen and low-vanadium D36 ship plate steel was observed by tansmission electron microscopy and the effect of precipitation strengthening was discussed.The results indicate that the microstructure of the steel consists of ferrite and pearlite.Precipitates are observed in ferrite but have not been detected in pearlite.Within ferrite the precipitates of VCx with rectangular platelet shape present a uniform and dispersive distribution.The precipitates,with a（001）α-Fe habit plane exhibit the Baker-Nutting orientation relationship with matrix.The TEM observation also reveals the existence of a few sphericall shaped precipitate of V6C5（monoclinic system） having an orientation relationship with ferrite.It appears that the V6C5 phase is transformed from the coherent VCx by redistribution of carbon atoms.The precipitation strengthening increment is about 63 MPa in the low-nitrogen and low-vanadium steel containing 0.05%V.The strengthening effect of vanadium can be enhanced by high density dislocations in ferrite with addition of small amounts of niobium.

关 键 词：船板钢 析出相 沉淀强化 

分 类 号：TG111.5[金属学及工艺—物理冶金] TG113.25[金属学及工艺—金属学]