Analysis of the impact of QD08 steel barroughrolling process on core quality and process optimization
This study addresses the quality issues encountered by a steel company in actual production,such as loose core,porosity,and inclusions in QD08 steel bars.By combining on-site actual process parameters,finite element simulation analysis was conducted on the rough rolling process of QD08 special steel bars using MSC.Marc finite element software.The temperature field and equivalent plastic strain distribution of the rolled piece during the rough rolling process were deeply explored,and further research was conducted on the specific effects of factors such as dephosphorization time and heating temperature between the rolled piece and the roll on deformation penetration and core quality.Through regression analysis of the simulation results,it was found that when the tapping temperature is between 1 120～1 195℃ and the dephosphorization time is between 4～20 s,the deformation penetration and equivalent plastic strain of the core will increase with the increase of these parameters,thereby significantly increasing the welding rate of core porosity.Especially when the tapping temperature is 1195℃ and the dephosphorization time is 12 s,compared to the conditions of tapping temperature at 1 120℃ and dephosphorization time at 4 s,the temperature difference between the core and surface can increase to 122.8 ℃,the equivalent plastic strain of the core significantly increases to 2.29996,and the welding rate of core porosity defects increases by 26％.Field rolling experiments using cast billets of similar heat numbers showed that when using the current original process parameters,the internal damage rate can reach 4％;however,by improving the rolling process parameters,such as increasing the starting rolling temperature by 39 ℃,internal damage can be completely eliminated;further increasing the dephosphorization time by 2 s on this basis can also completely eliminate internal damage.The above field experimental results verify the accuracy of the simulation analysis and provide important guidance for controlling the internal damage rate in actual production.
万方数据
维普
