摘要
铌、钛微合金化钢连铸坯高温变形试样中主要有三类碳、氮化合物析出：（１）高温下析出的粗大块状ＴｉＮ析出物；（２）９５０～９００℃区间沿晶界和在晶粒基体内部析出的微细Ｎｂ（Ｃ，Ｎ）动态析出物；（３）温度低于９００℃后Ｎｂ（Ｃ，Ｎ）依附在ＴｉＮ颗粒上生成的复合析出物．在９５０～９００℃区间析出的微细Ｎｂ（Ｃ，Ｎ）是造成此温度区间试样延塑性急剧降低的主要原因．由于氮优先与钛反应，减少了低温时Ｎｂ（Ｃ，Ｎ）和ＡｌＮ的析出量，使铌、钛微合金化钢在８５０℃Ｃ～Ａｒ３温度之间延塑性没有进一步降低．
Three types of precipitates were found in the high temperture tensiled Nb and Ti alloying steel CC slab specimens. One was the block shaped coarse TiN particles precipitated at higher temperature. Another type was the fine Nb(C,N) dynamic precipitation products at 950～900℃,which brought about remarkable ductility reduction of the steel in this temperature region. The third type was the coexisted precipitates of Nb(C,N) and TiN formed at temperature lower than 900℃ by fine Nb(C,N) nucleating and growing on TiN particles. As Ti preferentially combined with N at higher temperature which suppressed the formation of the detrimental AlN precipitates at lower temperature. There was no ductility drop for Nb Ti steel at temperature between 850℃ and A r3 .
出处
《化工冶金》
CSCD
北大核心
1997年第3期273-276,共4页
关键词
铌
钛
微合金化钢
连铸坯
碳化物
氮化物
析出
Nb Ti micro alloying steel, Continuous casting strand slabs, Carbide,Nitride,Precipitation
