Research Of Low Temperature Annealing Mechanical Properties And Plate Flatness On300Series Stainless Steel Strip

With the constantly development of the world industrial, more and more high to therequirement of stainless steel at home and abroad，more and more strict to the quality ofstainless steel in a variety of industrials, so strip flatness and properties control of stainlesssteel strip shape are the premise condition that meet the industry further development.In this paper，aim at an enterprise’s cold rolled304austenitic stainless steelproduction process of poor flatness and poor product performance and product yield low,based on the existing equipment12roll650double frame reversing cold rolling mill andcontinuous low temperature stress annealing furnace，researched stainless steel stripinternal residual stress distribution under different rolling technology and annealingprocess，microstructure change、mechanical properties change rule and so on.Through different heat treating system studies annealing process to have an effect onthe microstructure and mechanical properties of304stainless steel strip. Results show thatdifferent annealing process has a large influence on mechanical properties of this steel strip,at same annealing tension and cooling velocity, when annealing temperature ranges from450℃to600℃,the R0.2, Rmand HV of material indoor temperature structure changing riseafter the fall，and at annealing furnace temperature550℃, the R0.2、Rmand HV reachesmaximum. through the annealing temperature studies strip flatness and mechanicalproperties of cold rolled304stainless steel, the blind hole method is adopted in this papermeasured the surface residual stress of cold rolled304stainless steel that reveals therelations with steel plate flatness and residual stress, test and analyzes the mechanicsproperties of stainless steel belt under different annealing temperature by tensile testmachine. Results show that the yield strength and tensile strength changing rise after thefall of first with the increase of annealing temperature,304stainless steel yield strengthand tensile strength values most when annealing temperature is500℃, tension ofannealing in9kgf/mm2, simultaneously, the internal residual stress distribution of stainlesssteel with the most uniform, shows that mechanical properties and optimum flatness of304 stainless steel is best at500℃annealing. aim at yield strength of stainless steel strip in theprocess of low temperature annealing is not easy to control, in this paper, the301Bstainless steel annealing process was studied, and found that the pressure ratio of rollingprocess, annealing temperature and material thickness is the key factors influencing yieldstrength in low temperature annealing of stainless steel strip. Training by BP algorithm ofartificial neural network, Using the model which obtained from the training of yieldstrength after low temperature annealing were analyzed and predicted. Through calculationshows that the relative error of predicted yield strength and the actual yield strengthbetween-5.76%to5.59%,through building predicted atlas analysis shows that, rollingprocess reduction rate and annealing temperature have a high ability to adjust for materialyield strength, incoming thickness has a little ability to adjust for yield strength.In the paper, research result successfully control the mechanical properties of stainlesssteel strip to achieve user required a variety of mechanical properties indexes, to planreasonable technological parameter for this enterprise and to bring striking benefit ofproduction.