Production Process Optimization Of Low Carbon Stamping Steel Plate And Hot Rolled Microstructure Grain Size Controll

With the rapid development of China's economy,low-carbon stamping steel sheets are widely used in various industries such as automobiles,home appliances,building materials,home decoration,stationery,furniture,etc.,and the research on steel materials is getting deeper and deeper.Since 2008,GF has gradually developed low-carbon stamping steel.According to the equipment conditions of the production line,it has gradually developed SPHD,SPHE,IF.After cold rolling and annealing,the products are used in auto parts.In this paper,the whole process technology analysis and improvement are carried out from the steelmaking-hot rolling-cold rolling-annealing process,and the whole process production system of GF low carbon stamping steel is formed.The main research contents and results are as follows:(1)Around the stamping of low carbon steel in data query and lab test,determination of the dynamic CCT curve of low carbon steel stamping and determine the phase transition temperature range within the scope of the 50?,and on the basis of preliminary made the TMCP of stamping steel production process,provides a theoretical guidance for industrial trial production.(2)According to the JIS Japan standard,according to the customer's product use and material technical requirements,combined with the process equipment capacity of the factory,the chemical composition control range(C:?0.04%)of the low carbon stamping steel and the hot rolling process trial production plan are gradually formed.(3)According to the problems in the production trial production and customer trial process,through the sample test and organization and performance analysis,the hot rolling process and cold rolling process are optimized continuously,and the production process system of low-carbon stamping steel is finally determined.That is,the content control range of C:SPHD=0.030%,SPHE=0.010%;Hot rolling process,finishing temperature 900-930?,coiling temperature 570-590?;Cold rolling process:soaking temperature 680-700?;The heat preservation time is 20h.(4)Aiming at the inhomogeneity of microstructure grain size in different parts of hot rolled plate encountered in the production process,laminar cooling equipment was optimized and controlled to effectively reduce the inhomogeneity of microstructure grain size in hot rolled plate.The range of grain size within grade 2 is conducive to improving the forming performance index of cold rolled product.