| Fine blanking technology studied in this paper refers to the power and pressure margin fine blanking technology under three-dimensional power , This technology is a kind of precision machining craft developed on the basis of ordinary stamping, which pertains to a new field in the development of blanking technology. it has fundamentally changed the metal material processing chain, and it is a high quality, efficient, high value-added machining craft. But fine blanking formative process has very complex mechanisms, accompanied by a series of physical phenomena, these phenomena affect the final shape stress, strain, temperature distribution and product performance,so fine blanking in the formative mechanisms of research is difficult to achieve a major breakthrough, which seriously impedes fine blanking technological development, especially for domestically produced thick steel in the field of fine blanking.This article does research on the domestic steel by using experimental techniques and simulation techniques, analyzing the relationship between quality of thick fine blanking pieces and technological parameters as well as deformation mechanisms of fine blanking,providing some theoretical basis and practical basis for the domestic technical development about fine blanking of thick.Targets of this study are fine blanking parts chosen from Wuhan Huaxia Fine-blanking Technology co.,Ltd, the mould required for experiment is designed by the author , its single die clearance is 0.02mm, and it is double gear loop structure. without being annealed Q235 which has thickness of 3.5mm, 5mm, 6mm and 7mm and 45steel with thickness of 4mm, 6mm are tried to be blanked in this mould. and analyzes blanking and punching sheared-ray section, die-roll burr change of size on both sides ,warp degrees and die-roll size ect. fine blanking part quality factors by the technical parameters, such as blank holder-pressure, anti-pressure, the relative blanking gap, thickness. Meantime, the article gets the best copulate proportion between anti-pressure and blank holder- pressure power in allusion to domestic steel without being annealed. Draw. And the introduction of hardness analysis and metallography laboratory is to study the material flow situation and hardness status in the process of fine blanking deformation.This article analyzed parameters affecting the material plasticity flow in the process of fine blanking and deformation from the perspective of Plasticity mechanics, and mainly analyzed various factors affecting static hydraulic pressure in the area of fine blanking and deformation. Simultaneously this paper introduces firm plasticity finited element method to carry through Numerical Simulation of thick fine blanking,and upbuilded a reasonable simulation model of fine blanking , separate process of pressing gear loop from blanking process. DEFOEM-2D is used to simulate the process of deformation and fine blanking in order to acquire field of stress and strain at different stages of anamorphic process, at the same time obtained corner radius R of different concave modules and over angle α field of static hydraulic pressure in the area of deformation ,The results of Simulation accorded with analysis results of hardness and metallography laboratory, the amount and distributionof static hydraulic pressure tallied with analysis of fine blanking theory , and helped to improve sheared face quality , so it is feasible to make use of simulation software DEF0RM-2D to simulate fine blanking deformation, and also can provide theoretical basis for instituting fine blanking craft and die design.
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