Effect Of Hot Rolled Annealing Process On Microstructure,texture And Properties Of Tin-bearing Ferritic Stainless Steel

In recent years,the supply of nickel resources and price fluctuations have become an important reason for restricting the healthy and stable development of stainless steel.At present,it has been found that the addition of tin element in ferritic stainless steel can improve the corrosion resistance and the formability of stainless steel.At the same time,it is also helpful to promote the variety structure optimization and technological progress of stainless steel industry,and significantly reduce the dependence degree of external precious alloy resources,so it has good prospects for development.However,there is little research on the effect of hot rolled annealing on the properties of tin-bearing ferritic stainless steel.Therefore,the influence mechanism of hot rolled annealing process on microstructure,texture and properties of ferritic stainless steel with Sn is discussed from the perspective of microstructure evolution and texture evolution.It has important theoretical guiding significance and practical application value for developing tin-bearing ferritic stainless steel production technology with excellent formability and corrosion resistance and improving the forming and corrosion resistance of tin-bearing ferritic stainless steel.In this paper,metallographic observation,SEM characterization,mechanical properties testing,EBSD testing and electrochemical measurement were adopted to characterize hot rolled tin containing ferritic stainless steel microstructure,texture,mechanical properties,formability and impact resistant corrosion resistance,the main conclusions are summarized as follows:(1)For tin-bearing ferritic stainless steel,when the hot rolled annealing temperature reaches 900?,the cold rolled and annealed sheet has been fully recrystallized,but the grain size is small and the distribution is uneven.When the hot rolled annealing temperature rises to 950?,the recrystallized grain size increases and the microstructure is more uniform.(2)Tin bearing ferritic stainless steel is hot rolled and annealed in the range of 900?1000?,the cold rolled sheets are composed of strong ?-fiber texture and weak y-fiber texture.With the increase of the annealing temperature of hot rolled,the intensity of the texture of ?-fiber and ?-fiber of the cold rolled sheets increased gradually.The strong point change path of a-fiber texture is:{114}<110>?{113}<110>?{112}<110>,and ?-fiber texture strength is still maintained a t{111}<110>;the y-fiber recrystalized texture strength of the cold rolled sheet increases first and then decreases.When the hot rolled annealing temperature rises to 950?,the strength of the recrystallized texture of the y-fiber reaches the maximum.(3)Tin-bearing ferritic stainless steel is hot rolled and annealed in the range of 900?1000?,when the hot rolled annealing temperature rises to 950?,the yield strength and tensile strength of the experimental steel are the highest,the maximum plastic strain ratio r reaches 1.386,the minimum of the ear coefficient of ?r is 0.560.At the same time,the surface resistance to wrinkle is the best,with excellent mechanical properties and 'formabilities.(4)Uniform corrosion,pitting corrosion and electrochemical test(pitting corrosion)were carried out on the cold rolled annealed sheets of Sn bearing stainless steel,which were annealed at 900?,950?,1000? respectively.The results show that:because of the micro structure of cold rolled annealed sheet with hot rolled and annealing temperature is 950?,the microstructure is the most uniform,the degree of equiaxed is high,and the concentration of defects is less,so the corrosion resistance of the cold rolled annealed sheet is the most strongest.