1 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China 2 Shougang Jingtang Iron and Steel United Co., Ltd., Tangshan 063200, Hebei, China
Flexible manufacturing technology of controlling exact bake hardening value in continuous galvanizing line
1 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China 2 Shougang Jingtang Iron and Steel United Co., Ltd., Tangshan 063200, Hebei, China
摘要 Flexible manufacturing technology for ultra-low-carbon bake hardening (BH) steels with different solute carbon contents in the range of (6–16) × 10-4 wt.% was systematically studied. The effects of soaking temperature, cooling rate and aging time on solute carbon content were explored. The bake hardening value in a continuous galvanizing line with an over-aging section was investigated. Optimal manufacturing parameters were calculated using the design of experiment to obtain the best and most flexible process parameters. Results indicate a relationship among carbon content, soaking temperature and cooling rate. When solute carbon is 9 × 10-6, cooling rate is 50 °C/s, the soaking temperature is 745 °C, and BH value is 45 MPa, the requirements of an automobile factory can be met.
Abstract：Flexible manufacturing technology for ultra-low-carbon bake hardening (BH) steels with different solute carbon contents in the range of (6–16) × 10-4 wt.% was systematically studied. The effects of soaking temperature, cooling rate and aging time on solute carbon content were explored. The bake hardening value in a continuous galvanizing line with an over-aging section was investigated. Optimal manufacturing parameters were calculated using the design of experiment to obtain the best and most flexible process parameters. Results indicate a relationship among carbon content, soaking temperature and cooling rate. When solute carbon is 9 × 10-6, cooling rate is 50 °C/s, the soaking temperature is 745 °C, and BH value is 45 MPa, the requirements of an automobile factory can be met.
ZHENG Xiao-Fei. Flexible manufacturing technology of controlling exact bake hardening value in continuous galvanizing line[J]. Journal of Iron and Steel Research International, 2018, 25(12): 1296-1302.
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2018, Vol. 25 
