The Technology Research Of Investigation Of Homogenizing Rolling At Non-uniform Temperature

Deformation of thick steel plate and large size wire along the thickness direction was non-uniform during the traditional hot rolling,with which was a small compression ratio in center,as a result of uneven internal organization and low magnification,the downstream customers could not produce the high-end products.This paper studied uniformity of the deformation of thick steel plate and large size wire with the method of non-uniform temperature rolling.This paper studied the method of non-uniform temperature rolling and the traditional hot rolling by means of physical simulation techniques and numerical simulation techniques,GCr15 bearing as the research material.At first,the method of non-uniform temperature rolling at laboratory with Gleeble-3800 thermal simulation testing machine was studied.The microscopic observation and hardness measurement of different rolling pass was proved by the thermal simulation testing experiment in Gleeble-3800 system.Results indicated that the process with the non-uniform temperature rolling is favor of increasing strain and refinement of grain size in the center of GCr15 bearing steel,the maximum percentage of refinement was 78.6%.Secondly,the thick plate rolling model and GCr15 bearing steel rolling model are established by means of DEFORM finite element software.This part researched the method of non-uniform temperature rolling which the slab is sprayed quickly to form a non-uniform temperature field in the thickness direction.The temperature field and strain field in the thickness direction of rolling was predicted and compared with traditional processes.The result on simulation and experiment show that the problems of low-fold tissue defects is improved by non-uniform temperature rolling.At last,this paper studied dynamic recrystallization behavior under the condition with non-uniform temperature rolling by the finite element software,the result of simulation same as the above study.This paper studied the method of non-uniform temperature rolling to use a variety of means,the result of simulation and experiment show that the method of non-uniform temperature rolling could improve uniformity of the deformation of thick steel plate and large size wire.Forming a non-uniform temperature field in the thickness direction of rolling and a uniform strain field in the thickness direction of rolling to use reasonable cooling process before rolling,so the downstream customers could produce the high-end products.