Research On Microstructure And Properties Of DC03EK Enamel Sheet Steel

Enamel products are loved by the masses because of their lightness, durable, artistic and healthy. The quality of enamel products has closely relationship with the quality of embryo medals. For our nation, the research of cold rolled sheet steel for enameling stated late. Until now for internal, large steel enterprises and some scientific organizations had many researches on cold rolled sheet steel for enameling which is used for deep drawing or extremely deep drawing, mostly using ultra low carbon steel and adding Nb, V, Ti and RE etc., however, the amount of researches on those which has the carbon content between0.01%～0.05%with little or without alloy elements used for common drawing is less. Therefore, this research develops DC03EK enamel sheet steel used for common drawing. To obtain good properties by using sensible content designment and rolling, annealing processing, provide basis for industry produce, achieve the completeness of types and standards for our nation’s steel industry.This research mainly studied the effect of hot rolling processing (finishing temperature and coiling temperature), cold rolling processing (reduction) and annealing processing (annealing temperature) on microstructure and properties of DC03EK, meanwhile, examined its enameling and adherence properties, obtained the following conclusion:(1) Experimental steel is good to be hot rolled under high finishing and coiling temperature. Under high coiling temperature, Fe3C on the ferrite grain boundaries is thick and there are many decentralized rotund or near rotund MnS, there is BN assembled in03B experimental steel.(2) Experimental steel is good to be cold rolled by the reduction more than70%, thick Fe3C and nonmetal mixture can be smashed to pieces. Meanwhile, large reduction can reduce recrystallization temperature and so can the addness of the element B.(3) Along with the annealing temperature rises, the grain size of the experimental steel gets bigger gradually, strength become lower, percentage elongation after structure gets larger. The n value of experimental steel changes little along with the annealing temperature changes, r value gets higher along with the annealing temperature rises. When annealing temperature is 730℃, the experimental steel can gain its best forming properties, yield strength reached that demanded under240MPa, tensile strength conform with demanded270MPa-370MPa, percentage elongation after structure reached that demanded more than34%, n value reached0.25, r value reached1.5, simulate forming test can alse reached the demand, the experimental steel has good properties of formability.(4) For experimental steel after annealing of730℃for5hours under reduction of80%, the average grain intercept is10μm～11μm, grain-size number is9.5-10. There are many decentralized rotund or near rotund MnS and Fe3C in the ferrite grain which can make holes between ferrite, become hydrogen trap, rise fish scale resistance.(5) The hydrogen permeate time of experimental steel can reach the demand, there is no fish scale after enameling for72hours, it has good fish scale resistance. The result of adherence test outstrips the products demand. The combination between porcelain and steel is inseparable, it has good adherence properties.