STUDY ON THE EFFECT OF SECONDARY BANDED STRUCTURE ON THE FATIGUE PROPERTY OF NON-QUENCHED AND TEMPERED MICRO ALLOYED STEEL
Due to composition segregation and cooling speed,streamline or banded structure were often obtained in the thermal forming parts along the direction of parts forming.Generally speaking,banded structure doesn”t decrease the longitudinal mechanical properties,so the secondary banded structure can”t get enough attention.The effect of secondary banded structure on the fatigue properties of micro alloyed DG20Mn and 35CrMo steel was investigated using the axial tensile fatigue test of stress ratio of 0.1.The result shows that secondary banded structure was obtained in the center of the steel parts,because of the composition segregation and the lower cooling rate in center part of steel.Secondary banded structure has no significant effect on axial tensile properties of both DG20Mn and 35CrMo,but decreases the axial tensile fatigue performance of DG20Mn steel.This study suggests that under the high cyclic tensile stress,multi-source damage cracks in steel initiated by large strain of pearlite of secondary banded structure,which is larger than damage strain,is the major factor of the decrease of fatigue life of steel.
secondary banded structure micro alloyed steel damage strain fatigue performance
Cheng Yajie Liao Qingliang Zhang Yue
School of Materials Science and Engineering,University of Science and Technology Beijing,30 College School of Materials Science and Engineering,University of Science and Technology Beijing,30 College
国内会议
杭州
英文
641-647
2015-11-11（万方平台首次上网日期，不代表论文的发表时间）