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| Investigation of Surface Crack on Micro-Alloyed Steel Plate by DHCR |
| LIU Zhi-ming,ZHANG Jiong-ming,LUO Yan-zhao |
| School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China |
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Abstract In order to find out the cause of surface cracks for the same batches slab, surface crack on micro-alloyed steel plate produced by direct hot charging process was investigated by means of metallographic analysis, scanning electron microscopy, energy spectrometer analysis and transmission electron microscopy, and compared with crack-free plate produced by cool charging process. The results show that the main factors of surface crack on micro-alloyed steel plate produced by direct hot charging process are the segregation of low melting point elements such as Cu, As in slab’s cooling or heating process. Compared with hot-rolled plates produced by hot charging, the grain size of cold charged rolled plate about 10μm in diameter, while the grain size of hot-rolled plates by hot charging are large and uneven. Precipitates of hot plate are between 15 -25nm in size, the crack source are more than the matrix and a large amount of fine Nb(CN) precipitate at the boundary of the austenite grains, which decreases the strength of the grain boundary sharply.
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Received: 06 December 2010
Published: 20 February 2012
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| [1] |
AI Ke-nan, ZHANG Pan-pan, ZHAO Meng-hao, LI Cheng-liang, ZHANG Zhi-ming, FU Jian-xun. Analysis of formation mechanism of surface crack of 1215 free-cutting steel during drawing[J]. Iron and Steel, 2020, 55(2): 88-94. |
| [2] |
LIN Peng，ZHANG Hong-cai，LIU Ying，XU Zheng-zhou. Cause analysis of surface crack defects of gear steel 20CrNiMo rolled product[J]. PHYSICS EXAMINATION AND TESTING, 2020, 38(2): 40-. |
| [3] |
LIU Xiang，DU Qunli，LI Xin. Effect of heating process on grain growth of#br#
NbTi microalloyed steel[J]. Iron and Steel, 2019, 54(9): 116-120. |
| [4] |
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| [5] |
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| [6] |
LIU Xuhui，LI Guanghui，LIU Zhenyu. Effects of cooling process on microstructure and #br# mechanical properties in a V-Ti bearing steel[J]. Iron and Steel, 2019, 54(7): 77-82. |
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2012, Vol. 47 
