20CrMnTi 钢的位错密度及晶体结构 - 吉林大学学报.PDF

第 34 卷第1 期 Vo l. 34 No.l 吉林大学学报(工学版) 2004 年 1 月 Journal of Jilin University (Engineering and Technology Edition) Jan.2004 文章编号: 1671 - 5497(2004 )01 - 0031 - 04 20CrMnTi 钢的位错密度及晶体结构 程万军1 高占民2 黄良驹2 (1.吉林大学材料科学与工程学院，吉林长春 130025; 2. 吉林大学辑锻工艺研究所，吉林长春 130025) 摘 要:采用 X 射线衍射法及新的线性分析理论，准确地测量了不同应变量时 20CrMnTi 钢的 位错密度，分析了应变量与位错密度的关系。结果表明:位错密度随变形量的增加而提高，退 火状态时位错密度较低。透射电镜试验证明了 20CrMnTi 退火后的组织为铁素体和珠光体， 晶内位错表态为曲折形的位错线，变形后形成胞状结构，同时有孪晶出现。胞状结构的出现 大大提高了钢的强度。 关键词 :20CrMnTi 钢 jX 射线衍射;位错密度;晶体结构;位错形态 中图分类号:TG144 文献标识码:A Determination of dislocation densities and crystal structure on 20CrMnTi steel 1 2 2 CHENG Wan-jun , GAO Zhan-min , HUANG Liang-ju (1. College of Material Science and Engineering , Jilin University , Changchun 130025 , China; 2. Roll Forging Institute , Jilin University , Changchun 130025 , China) Abstract: Dislocation densities in 20CrMnTi steel under different sizes of strain were determined exactly by X-ray diffraction method and a new profile analysis theory. The relation of strain and dislocation densities was analyzed. The results show that the increase of dislocation density is accompanied by the increase of deformation amount. The dislocation density has lower value when the steel is ann巳aled. TEM tests prove that 20CrMnTi become ferrite and pearlite after ann巳aling. Intragranular dislocation appears as zigzag dislocation line and comes into being cell structure with the appearance of twin crystals after deformation. Cell structure improves the strength. of st巳el greatly. K