摘要
采用物理化学相分析、场发射透射电镜等手段研究了正火过程中管线钢中V、Ti微合金元素的析出行为,并讨论了该行为对管线钢性能产生的影响。结果表明,正火过程中多数Ti元素以富Ti或富V的(Ti,V)C或(Ti,V)(C,N)形式存在,冷却过程未发生含Ti第二相的析出;V元素在正火保温过程中多数呈固溶态,在冷却过程中仅有少量VC以保温过程中未溶解的(Ti,V)C或(Ti,V)(C,N)为核心产生沉淀并互溶,形成呈圆形的富V析出相;由于VC的析出量较少,未产生较强的析出强化作用,使得正火态试样强度低于轧态试样,而VC析出对铁素体晶粒产生的细化作用使得正火试样低温韧性优于轧态。
Behavior of precipitates containing V and Ti in pipeline steel during normalizing process was studied by means of physicochemical phase analysis and field emission TEM,and the effect of precipitation behavior on the properties of the pipeline steel was discussed.The results indicate that most of Ti element exists in the form of(Ti,V)C or(Ti,V)(C,N)which is Ti-rich or V-rich,and the secondary phase containing Ti doesn’t precipite during cooling process.Most V element is in solid solution during the austenitizing process for normalizing,and only little VC precipitates with the(Ti,V)C or(Ti,V)(C,N)undissolved as the nuclei during the austenitizing,and forms circular V-rich precipitates.Because of the less VC precipitate,no strong precipitation strengthening effect is produced,which result in the strength of the rolled specimen higher than that of the normalized specimen.The refinement effect of VC precipitation on the ferrite grain makes the normalized specimen have better low temperature toughness than the as-rolled state.
作者
张海
李少坡
丁文华
Zhang Hai;Li Shaopo;Ding Wenhua(Shougang Group Co.,Ltd.,Research Institute of Technology,Beijing100041,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2019年第10期162-165,共4页
Heat Treatment of Metals
关键词
管线钢
正火处理
微合金元素
析出相
pipeline steel
normalizing
microalloying element
precipitates
