材料期刊网

摘要：采用热模拟及透射电子显微镜结合纳米束能谱技术，研究了Mn-Mo-Nb-B等多元微合金钢奥氏体变形后等温过程中（松弛）的析出行为。实验结果表明：经变形后，在850℃和900℃保温过程中，Mn-Mo-Nb-B多元微合金钢析出颗粒尺寸在各个阶段均小于相同工艺下Nb-Ti钢中析出相的尺寸。统计结果显示，析出颗粒的尺寸分布均复合正态分布，并且峰位尺寸接近平均尺寸。析出相中Nb/Ti比随着松弛时间而增大。松弛阶段后期，Mo进入(Ti,Nb)(C,N)的晶格当中，其含量随着时间的延长而增加。 关键词：Mn-Mo-Nb-B微合金钢；等温松弛；应变诱导析出；碳氮化物

Abstract: Thermo-simulation test, transmission electron microscopy(TEM) and nanobeam EDS technique were used to investigate the strain induced precipitation behavior during relaxation process after deformed austenite in Mn-Mo-Nb-B low carbon multi-microalloyed Steel. The experiment results indicate that during isothermal holding at 850℃and 900℃ after predeformation, the size of precipitates occurred in the Mn-Mo-Nb-B steel at the different stage are smaller than that happened in the only Nb and Ti-bearing microalloyed steel. The results of statistics show that the distribution of particle size corresponds to the normal one and the peak size approaching to the mean value. The ratio of Nb/Ti of precipitates increased with the relaxing time. After longer holding, Mo atoms would enter the lattice of (Nb,Ti)(C,N) precipitates and its concentration in the precipitates increased with the relaxation time prolonged. Keywords: Mn-Mo-Nb-B microalloyed steel; relaxation; strain-induced precipitation; carbonitrides