Nb-Ti微合金钢中第二相的溶解行为  

Dissolution Behavior of Second Phase in Nb-Ti Microalloyed Steel

作　　者：李敬[1] 苑少强[1] 褚祥治[1] 

机构地区：[1]唐山学院机电工程系,河北唐山063000

出　　处：《铸造技术》2017年第9期2087-2089,2095,共4页Foundry Technology

基　　金：河北省杰出青年科学基金资助项目(E2012105005);河北省教育厅资助项目(QN2014337)

摘　　要：利用碳萃取复型、TEM和EDX分析,研究了低碳Nb-Ti微合金钢在1 300℃等温过程中第二相粒子的溶解行为。实验结果表明:钢中有两类尺度存在显著差异的析出颗粒,其一为尺寸在50 nm以上的富钛相(生成于钢液凝固阶段),其二为尺寸小于20 nm的富铌相(形成于奥氏体变形过程)。在1 300℃保温2 h后,应变诱导析出相基本消失,而凝固过程中形成的析出相在保温48 h后,还存在含Nb的(Nb,Ti)(C,N)复合相。在微合金钢中含Ti的情况下,碳氮化物的稳定性大幅提高。这些结果表明,析出相的形成和热稳定性在很大程度上取决于Nb和Ti原子的相互作用。The dissolution behavior of the second phase particles in low carbon Nb-Ti microalloyed steel during isothermal treatment at 1 300 ℃was investigated by carbon extraction replica, transmission electron microscope and energy dispersive X-ray detector analysis. The experimental results show that there are two types of precipitate particles with significant scale differences, one is the Ti-rich phase above 50 nm in size （generated in the liquid steelsolidification stage）, the other is the Nb-rich phase less than 20 nm in size （formed in the austenite deformation process）. The precipitation phase induced by strain basically disappears at 1 3,00 ℃for 2 h, but there are still some （Nb,Ti） （C,N） composite phases at 1 300℃for 48 h, these （Nb,Ti） （C,N） composite phases form in the solidification process. In the case of microalloyed steel containing Ti, the stability of carbonitride greatly improves. These results indicate that the formation and thermal stability of the precipitated phase strongly depend on the interaction of Nb and Ti atoms,

关 键 词：NB-TI微合金钢 碳氮化物 溶解 热稳定性 

分 类 号：TG142.1[一般工业技术—材料科学与工程]