快速加热连续退火对超高强TRIP钢显微组织与力学性能的影响  

EFFECTS OF RAPID HEATING CONTINUOUS ANNEAL ING ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF ULTRA HIGH-STRENGTH TRIP-AIDED STEEL

作　　者：许云波[1] 侯晓英[1] 王业勤[2] 吴迪[1] 

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,沈阳110819 [2]莱芜钢铁集团有限公司,莱芜271104

出　　处：《金属学报》2012年第2期176-182,共7页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目51174059;国家重点基础研究发展计划项目2011CB606306;中央高校基本科研业务费专项项目N110407003资助~~

摘　　要：研究了快速加热连续退火工艺对V微合金化低Si含P系TRIP钢显微组织特征与力学性能的影响.结果表明,快速连续退火过程中,随着退火温度的升高,拉伸强度增加明显,然而为了保证其综合性能,并不能一味地提高其临界退火温度.加热速率80℃/s,退火温度为880℃时,残余奥氏体形态不仅仅局限于细小的块状结构;而且在贝氏体铁素体板条间能观察到大量的薄膜状残余奥氏体.细小、弥散的V(C,N))分布于铁素体或贝氏体基体中,大部分析出粒子直径在4—9 nm之间,实验钢具有优异的强度与塑性配合:R_m=1010 MPa,R_(P0.2)=690 MPa,δ=23.6%,n=0.27,r=1.17,强塑积达到23836 MPa.%.退火温度过高或过低,都会减少残余奥氏体的体积分数、改变其形貌并增大其尺寸,导致综合力学性能下降.The effects of rapid heating continuous annealing on microstructure and mechanical properties of ultra-high strength and low silicon TRIP steel containing phosphorus and vanadium were investigated.The results show that the yield and tensile strengths are increased with increasing inter- critical annealing temperature during rapid continuous annealing.However,the intercritical annealing temperature can not increase blindly to ensure its excellent combined mechanical properties.When the heating rate is 80°C/s and intercritical annealing temperature is 880°C,the retained austenite not only contains fine blocky structure,but also a large amount of interlath retained austenite films. A great amount of V（C,N） precipitates exists within ferritic matrix,and the sizes of most of the precipates are in the range from 4 to 9 nm.The tested steel has excellent mechanical properties：Rm = 1010 MPa,-Rp0.2=690 MPa,（5=23.6%,n=0.27,r=1.17,the product of strength and ductility（Rm xS） is 23836 MPa-%.If the intercritical annealing temperature is too high or too low,the comprehensive mechanical properties will be deteriorated since the volume fraction of retained austenite reduces, morphology changes and its size increase.

关 键 词：含V TRIP钢 快速加热 连续退火 力学性能 残余奥氏体 

分 类 号：TG111[金属学及工艺—物理冶金]