Study On Key Technology Of Hot-dip Galvanized Steel Strip Production For Guofeng IF Steel

IF steel is commonly known as Interstitial-Free Steel,sometimes is called ultra-low carbon steel,compared to common SPHC steel,it has a very good plastic deformation ability and no timeliness,especially it has low yield strength and very high Elongation,make this steel have excellent deep drawing performance,the performance can make a lot of difficult parts and deep stamping parts form at one time,so IF steel is welcomed by the automotive,home appliances,machinery and other industries.At present,Guofeng company has an pickling-tandem cold mill and hot galvanizing line,it can stably produce SPHC steel,but do not has experience in the production of IF steel,so the zinc-free IF steel galvanized production technology is urgently needed.In this paper,the capacity of Guofeng pickling-tandem cold mill and hot galvanizing unit is analyzed,it contrary to the different characteristics between IF steel and SPHC steel to make sure whether it h as the capability of producing IF steel.On this basis,the initial identification production processes is fixed and take out the adjustment scheme of the key process parameters,rapid and stable production is guaranteed.The details are as follows:Comparing the chemical composition of IF steel materials with different design schemes,through production verification,comparison of microstructure,texture and properties,the composition scheme of IF steel materials is finally determined.According to SPHC trimming process,the hardness difference influence between the raw material and disc slitting was analyzed,the preliminary trimming process parameters of the IF steel is fixed.the appropriate trimming process parameters is fumbled by practice.Origin Calculation Model of Rolling Mill do not have similar IF Steel,By manually modifying,the model of IF steel is added,and the IF steel can be stably produced by continuously optimizing the tension parameters.In the range of hot galvanizing stove equipment capability,the key process parameters of the annealing furnace are optimized to meet the target mechanical properties.Under the premise of guaranteeing the surface quality,optimize the skin spss mill and tension levelling process to attain the best mechanical properties.