【摘要】 通过金相显微镜和透射电镜分析研究了退火态TWIP钢的微观结构特征。结果表明,经过600℃退火10min后钢中存在冷轧的纳米级变形孪晶及少量位错;分别在700、800、900和1000℃退火10min后,发现退火温度决定了退火孪晶的尺寸:随退火温度升高,退火孪晶尺寸增大。退火孪晶仅有少量在再结晶过程中产生,而大量的退火孪晶在再结晶结束后的晶粒长大过程中生成并长大。退火孪晶尺寸的大小影响了TWIP钢的力学性能,孪晶尺寸为2～5μm时,试验钢表现出高强度,此时抗拉强度可达840MPa;孪晶尺寸为30～50μm时,试验钢表现出高的伸长率,可达到84.0%,表现出充分的TWIP效应。更多还原

【Abstract】 Microstructure characteristics of annealed twinning-induced plasticity steel were investigated by means of optical microscope and transmission electron microscopy.The results show that some dislocations and nano-deformation twins appears in the steel after annealed at 600 ℃ for 10 min.Annealed at 700 ℃,800 ℃,900 ℃,1000 ℃ for 10 min,respectively,it is found that size of annealing twins is relate to annealing temperature,annealing twins grow with increase of annealing temperature.A few annealing twins appear in the course of recrystallization,a great amount of annealing twins come into being and grow after recrystallization.When annealing twins size are 2-5 μm,TWIP steel has higher strength,and its tensile strength researches to 840 MPa.While annealing twins size are 30-50 μm,TWIP steel exhibits excellent ductility owing to the twinning induced plasticity(TWIP)effect and its elongation is 84.0%.更多还原