|
|
|
| Effect of Temper on Microstructure and Mechanical Properties of Acicular Ferrite Steel |
| KANG Junyan，YU Wei，CHEN Yinli |
| National Engineering Research Center for Advanced Rolling Technology, University of Science and Technology Beijing， Beijing 100083， China |
|
|
|
|
Abstract The microstructure and properties of acicular ferrite steel tempered from 540 ℃ to 630 ℃ were studied. Compared with the steel as rolled, the yield strength of steel tempered at 630 ℃ was increased by 75 MPa, the mean elongation was decreased by 1.9% and the mean impact toughness was almost unchanged. By comparison of the microstructure and precipitates before and after tempering, it can be concluded that in tempered steel the intragranular dislocation density is lower and part of platelike subgrains is disappeared, but the mean size of precipitates is smaller. The mean size of precipitates becomes bigger with the raise of tempering temperature. After tempering at 630 ℃, the distribution frequency (f(D)) of precipitates in the range of 1～10 nm is increased by two to three times, the amount of precipitated niobium and vanadium was increased by 166.9% and 584.6% respectively. It is considered that the enhancement of strength is mainly due to the increase in number of small precipitates and disappearance of part of platelike subgrains.
|
|
Received: 01 January 1900
|
|
|
|
| [1] |
WEI Tong-yu, ZOU De-ning, ZHANG Ying-bo, CHEN Wan-wan. Effect of aluminum on microstructure and properties of high alumina ferritic heat resistant steel[J]. Iron and Steel, 2020, 55(6): 80-83. |
| [2] |
CAO Yan-guang, LI Zhao-dong, DING Can-can, ZHANG Jin-wen, YONG Qi-long, GAO Jian-bing. Effect of niobium addition on hardenability of high-speed railway axle steel[J]. Iron and Steel, 2020, 55(6): 107-112. |
| [3] |
HE Ya-yuan,LI Li-wei,YIN Yun-yang,DENG Zhao-jun. Evolution of microstructure and properties of thickness section of wearresistant steel[J]. JOURNAL OF IRON AND STEEL RESEARCH , 2020, 32(6): 512-518. |
| [4] |
LI Lan-xin1,WANG Min1,JUAN Rong-fei1,BAO Yan-ping1,YANG Jin2. Distribution characteristics of oxides and sulfide inclusions in key areas of gear steel forgings[J]. JOURNAL OF IRON AND STEEL RESEARCH , 2020, 32(5): 370-376. |
| [5] |
ZENG Ze-yun, LI Chang-rong, LI Zhi-ying, LIU Zhan-lin,LI Zheng-song, ZHAI Yong-qiang. Thermodynamic analysis of titanium precipitation in HRB500E seismic steel[J]. Iron and Steel, 2020, 55(5): 45-51. |
| [6] |
ZHAO Yun-peng, YU Chao, XIAO Hong, WU Zong-he, XU Peng-peng, XIE Hong-biao. Effect of pure iron interlayer on mechanical properties of hot rolled stainless steel clad plate[J]. Iron and Steel, 2020, 55(5): 73-79. |
|
|
|
|
2006, Vol. 41 