| Because of its own advantages,die steel plate has a huge market in automobile fetal manufacturing,household appliances,building materials,electronic communications and large electromechanical technical equipment production industries.In recent years,with the rapid development of industry,the market has higher and higher requirements for the size,specification and performance of die steel plate.With the increase of the size of the billet,its internal defects will be more and more,among which the most prominent is the hole type defects,if these defects can not be pressed together in the subsequent pressure processing process,it will affect the quality of the final product.At present,due to the limitations of the general pouring technology,the existence of cavity defects cannot be completely eliminated.In order to solve this problem,further research is needed to deeply understand the development trend of cavity defects during pressure machining and to seek the best solution.In this thesis,the H13 die steel is selected as the research object,and the hole defects are prefabricated in the blank.By means of physical simulation and numerical simulation,the evolution of hole defects in the forging and rolling deformation process is tested and analyzed.(1)Plastic mud with similar properties to hot steel was used as a physical simulation material to analyze the stress-strain changes near the hole defects,and predicted its closure by the deformation trend of the section;(2)The finite element simulation analysis of H13 material was carried out by Deform,and the influence of the cross section shape,temperature,friction coefficient,stress-strain and other influencing factors on the closure of core hole defects was obtained.(3)Comparing the results of physical simulation and numerical simulation,summarizing the law of hole closure,optimizing the shape of steel ingot,optimizing the deformation ratio of forging and rolling,and obtaining a process scheme with good internal quality. |
PDF Full Text Request