摘要
分别采用分离式Hopkinson压杆和MTS Landmark电液伺服疲劳试验机对冷轧退火态Fe-20Mn-3Al-3Si相变诱导塑性(transformation induced plasticity,TRIP)钢进行900 s^(-1)~3500s^(-1)范围内的动态冲击实验和应变速率为3×10^(-3)s^(-1)准静态压缩实验.采用X射线衍射技术(X-ray diffraction,XRD)、电子背散射衍射技术(electron backscatter diffraction,EBSD)和透射电镜(transmission electron microscope,TEM)等对变形试样的微观组织结构进行表征.结果表明,该TRIP钢表现出正应变速率敏感性,且动态冲击变形的屈服强度明显高于准静态变形的屈服强度.无论是在动态冲击样品还是准静态压缩样品中,都可以观察到大量的ε-马氏体和α'-马氏体,且动态冲击样品中ε-马氏体和α'-马氏体的体积分数明显低于准静态变形样品中ε-马氏体和α'-马氏体的体积分数.在动态冲击样品中,除了能观察到大量的ε-马氏体和α'-马氏体以外,也可以观察到大量的{1011}ε_(T)孪晶和{1012}ε_(T)孪晶,并且,{1011}ε_(T)孪晶和α'-马氏体之间的取向关系为(110)α'//(0002)ε_(T),<111>α'//<2110>ε_(T).
The dynamic impact test and quasi-static compression test of cold-rolled and annealed Fe20Mn3Al3Si transformation induced plasticity(TRIP)steel was conducted by the split-hopkinson pressure bar(SHPB)at high strain rates ranging from 650s^(-1)to 3800 s^(-1)and the MTS landmark tester at strain rate of 3×10^(-3)s^(-1),respectively.The microstructure of samples before and after impact was characterized using electron back scattering diffaction technology(EBSD)and transmission electron microscopy(TEM).The result reveal that the TRIP steel shows a positive strain rate during dynamic impact deformation,and the yield strength of dynamic impact deformation is obviously higher than that of quasi-static deformation.A large amount ofε-martensite and a'-martensite were.observed in both dynamic impact samples and quasi-static compression samples.The volume fraction of g-martensite and a'-martensite in dynamic impact samples is significantly lower than that in quasi-static deformation samples.In addition to a large number ofε-martensite and a'-martensite,a large number of{1011}ε_(T) twins and{1012}ε_(T) twins were also observed in dynamic impact samples.Moreover,the fixed orientation relationship between{1011}ε_(T) twins and a'-martensite can be expressed as(110)a'//(0002)ε_(T),<111>a'//<2110>ε_(T).
作者
沈书成
谢盼
刘春雨
伍翠兰
SHEN Shu-cheng;XIE Pan;LIU Chun-yu;WU Cui-Ian(Center for High-Resolution Electron Microscopy,College of Materials Science and Engineer,Hunan University,Changsha Hunan 410082;Pico Electron Microscopy Center,College of Materials Science and Engineering,Hainan University,Haikou Hainan 570228,China)
出处
《电子显微学报》
CAS
CSCD
北大核心
2023年第2期161-170,共10页
Journal of Chinese Electron Microscopy Society
基金
湖南省自然科学基金面上项目(No.2022JJ30146)
国家自然科学基金项目(Nos.51831004,51801060,52171006)。
