Solidification And Heat Transfer Of Slab And Mechanical Behavior Analysis During Straightening

The high temperature casting slab in the heat transfer and solidification and straightening with liquid-core process,is regarded as a material with properties of solid and liquid phase,and its temperature,stress,strain and strain rate coupled to each other,influenced mutually,related to the product quality and production efficiency.Therefore,the study of these two processes have important theoretical and practical significance.According to the actual production of an Iron and Steel company R9300 slab continuous casting machine,the FEM analysis of billet which thickness is 230 mm and width is 1000 mm have been carried out with the FEM software of MSC.Marc.(1)The heat transfer equations and the boundary conditions which are required in the simulation of temperature field are determined.With a reasonable assumptions and simplifications,an unsteady,three-dimensional model of solidification and heat transfer in continuous casting of slab has been developed in this thesis.Under impetus of the rigid body,along curved orbit,the billet runs to the front straightening.With the movement of slab,the appropriate thermal boundary conditions are applied.Finally,make the slab from straight to bend,find the temperature distribution and shell thickness of the various stages.(2)With a reasonable assumptions and simplifying,the thermal-mechanical coupled straightening model is established.The simulation results of temperature field are regarded as the thermal initial conditions.Ignore the deformation before straightening,initial stress and initial strain are defined as zero and which is the mechanical initial conditions.Slab moves with the rollers,adopt direct coupling method,simulate the straightening process with liquid core and find the distribution of temperature,stress, strain and strain rate.(3)Simulate the multi-point straightening with gravity,find the deformation Pointed out the role of gravity for the straightening rollers can not be ignored by comparing with the multi-point straightening.(4)In the same casting conditions,simulate the continuous straightening and compare results between multi-point straightening and continuous straightening. Manifest the superiority of continuous straightening accurately.