Study On ASP Al-Killed Cold-rolled Sheet DC04 Steel

The thesis regards ASP Al-killed cold-rolled sheet DC04 steel of Jinan Iron and Steel Company as the research object. The main aim of the research work is to satisfy the demand of the customers on deep-drawing properties of cold rolled sheet. The effect of main processing parameters. such as heating and coiling temperature in hot rolling, deformation rate and annealing temperature in cold rolling on microstructure and deep drawing properties of the strip were studied. The main works of this thesis are as follows:1)The main task in steel making process are to decrease carbon and sulfur to increase steel purification, to optimize pre-treatment of iron liquid, to improve the re-blowing. In RH refining process, main research is on de-carbon process, internal control composition of keeping stable, continuous casting process. Based on the above method, the continuous casting slab with reasonable controlled composition, purified steel quality and good surface quality were gotten.2)In hot rolling stage, the main work is to control the second phase solid solution and segregation of deep-drawing DC04 steel according to the equipment situation and control ability of Jinan steel hot rolling mill, and to setup optimized hot rolling temperature schedule for DC04 slab, such as finishing temperature and coiling temperature. By using the optimized schedule, the hot rolling coils with reasonable microstructure and grain size were gotten.3)In process of cold rolling and anneal, by doing many research works of lab and industrial test, the reasonable schedule of cold rolling deformation rate and hydrogen batch annealing process were determined.4)Deep drawing property of DC04 products was checked with simulation forming and in the workshop.