氮对AHPV10钢奥氏体中VC析出动力学的影响  

INFLUENCE OF NITROGEN ON PRECIPITATION KINETICS OF VANADIUM CARBIDE IN AUSTENITE OF AHPV10

作　　者：李小明[1] 钟海林[1] 王学兵[1] 吴立志 况春江[1] 

机构地区：[1]安泰科技股份有限公司,北京100081 [2]河冶科技股份有限公司,石家庄50031

出　　处：《粉末冶金工业》2012年第6期11-16,共6页Powder Metallurgy Industry

基　　金：国家"十一五"科技支撑计划资助项目(2007BAE51B05);"863"计划资助项目(2012AA03A509)

摘　　要：以材料热力学及动力学为基础,以Fe-V-C-N四元系为研究对象,对比研究了1 130℃恒温条件下,碳化物VC及V(Cy,N1-y)在奥氏体中从形核、长大到熟化的连续过程。各元素在碳化物-基体界面处达到局部平衡,根据基体成分以及每个碳化物的大小分别计算出生长速度。当碳化物生长进入熟化阶段,在Gibbs-Thomson效应作用下,小颗粒开始回溶,大颗粒继续长大,表现为总颗粒数量减少,平均半径变大。结果表明氮主要参与碳化物的形核过程,并强烈促进碳化物的形核,使更多的细小碳化物生成,在熟化阶段,通过降低温度的方式可以抑制细小碳化物的回溶,从而达到最终细化碳化物的目的。Precipitation of vanadium carbides and vanadium carbonitrides in austenite in Fe-V- C-N system were studied under 1 130℃. On the basis of precipitation thermodynamics and ki- netics, continuous stages from nucleation to growth and coarsening of carbides were ana- lyzed. A local equilibrium condition was used at the precipitate-matrix interface to derive the growth rate of each precipitate as a function of its size and the current matrix composition. When coarsening occurs, small carbides began to dissolve and big ones keep on growing be- cause of the effect of Gibbs-Thomson, the radius of carbides increase while the number of carbides decrease. The results show that most of the nitrogen is consumed during the nuclea- tion stage, and strongly promote the nucleation of the carbides, as a result, more small car- bides are generated. During the coarsening stage, lowering the temperature can inhibit the small carbides from dissolving into the matrix, so the purpose of refining carbides can be a- chieved.

关 键 词：碳化物 析出 形核 热力学 动力学 

分 类 号：TG142.25[一般工业技术—材料科学与工程]