中文摘要：

对2种冷轧超低碳钢（Nb＋Ti—IF钢和高Nb—IF钢）进行了再结晶退火实验，对比研究了2种钢在超快速退火（加热速率约为300℃／s）下的再结晶组织和织构特征．结果表明，在超快速退火工艺下，含C和Nb量较高的Nb—IF钢再结晶平均晶粒尺寸与普通退火工艺下无明显差别（均为（11．0±0．3）μm），再结晶织构峰值{223}（472）的取向密度由普通退火工艺下的23．9降低到18．0，且织构类型分散．分析表明，较高的C和Nb含量在超快速退火工艺下推迟再结晶的发生，提高再结晶温度，增加了其非7取向形核所占比率，恶化（111）//ND取向织构，是其织构强度减弱的原因．在超快速退火工艺下，再结晶平均晶粒尺寸是否细化是高形核密度、极短的长大时间的晶粒细化效应与高晶界迁移速率的晶粒粗化效应相互竞争的结果，极大变形量和细晶作用产生的高形核密度造成形核点饱和，降低了超快速退火相对于普通退火工艺的晶粒细化效应，是晶粒细化不明显的主要因素．

英文摘要：

A new annealing technology has been developed in order to conduct fast steel anneal- ing. The microstructure and texture of the Nb＋Ti stabilized interstitial-free （IF） steel and high Nb-IF steel highly cold deformed to a reduction of 94.2% after ultra-rapid annealing （URA） process with heating rates approximately 300 ℃/s were characterized by means of OM, TEM, EBSD and XRD. The experimental results indicate that the recrystallization process is significantly accelerated and the finish recrystallization temperature is increased after URA. Moreover, the fully recrystallization can be obtained in as short as about 0.41 s, compared with about 4 s in the conventional annealing （CA） pro- cess with heating rates approximately 20° C/s. In the fully recrystallized condition, the grain size and intensity of {445}（231） fiber in the Nb＋Ti-IF steel, about 11.2 μm and 15.6, can be observed in one URA cycle, respectively. However, the grain size and intensity of {445}（231/ fiber are 13.5 μm and 14.0, respectively, after the Nb＋Ti-IF steel is subjected to one CA cycle. On the other hand, the URA has unapparently influence on grain size, within （11.0±0.3） μm in either one URA or one CA cycle, of the high Nb-IF steel, with about 18.0 intensity of {223} （472） fiber. Simultaneously, more random fiber can be found in one URA cycle than in one CA cycle with higher intensity of {223} （472） texture up to 23.9. The grain refining effect in either one URA or one CA cycle is attributed to the mutual interaction of nucleation density, annealing time and grain boundary migration rate.