CAJ | 학술논문

通过单轴热压缩试验，结合扫描电镜以及 X 射线衍射技术，研究了动态相变前奥氏体晶粒状态对基于动态相变的热轧Nb-V-Ti微合金化TRIP钢复相组织状态及力学性能的影响。与动态相变前奥氏体晶粒为等轴状条件下相比，动态相变前奥氏体晶粒为拉长状条件下，动态相变得到的铁素体转变量较大，最终复相组织中贝氏体含量较少且团径较小，马氏体含量较少，但对残余奥氏体含量及其含碳量影响不明显。与不含微合金化元素的基于动态相变的热轧 TRIP钢相比，Nb-V-Ti微合金化TRIP钢的屈服强度和抗拉强度明显提高，而延伸率有所降低。
통과단축열압축시험，결합소묘전경이급 X 사선연사기술，연구료동태상변전오씨체정립상태대기우동태상변적열알Nb-V-Ti미합금화TRIP강복상조직상태급역학성능적영향。여동태상변전오씨체정립위등축상조건하상비，동태상변전오씨체정립위랍장상조건하，동태상변득도적철소체전변량교대，최종복상조직중패씨체함량교소차단경교소，마씨체함량교소，단대잔여오씨체함량급기함탄량영향불명현。여불함미합금화원소적기우동태상변적열알 TRIP강상비，Nb-V-Ti미합금화TRIP강적굴복강도화항랍강도명현제고，이연신솔유소강저。
The influence of the state of prior austenite grains before dynamic transformation on the multi-phase microstructure and mechanical properties of hot-rolled Nb-V-Ti microalloyed TRIP steel based on dynamic transforma-tion of undercooled austenite (DTUA) was investigated by uniaxial hot compression test, scanning electron microscopy, and X-ray diffraction. In comparison with that prior austenite grains are equiaxed before DTUA, when prior austenite grains are elongated before DTUA, the volume fraction of ferrite obtained by DTUA is higher, the volume fractions of bainite and martensite are lower, and the average size of bainite packets is smaller in the final multi-phase microstructure. But the volume fraction of retained austenite and the carbon content of retained austenite are similar in both cases. Compared with hot-rolled TRIP steel based on DTUA without micro-alloying elements, hot-rolled Nb-V-Ti microalloyed TRIP steel based on DTUA demonstrate higher yield strength and tensile strength, but lower elongation.