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Fine blanking technology is a precision plastic forming technology , can be processed to obtain high dimensional accuracy , punching clear surface , warping small interchangeability good quality parts , and therefore are widely used in various industrial fields . Frequent repair and replacement with the fine blanking process and die structure is more complex, the mold development cycle is long , serious impact on production efficiency , fine blanking die life has become a bottleneck restricting the development of the industry . Therefore, the analysis of failure in the form of fine blanking die and mold structure optimization , thus extending the life of the mold , has a very important practical significance . This article first appeared for the the pawl , chute board two fine blanking die punch fracture from mechanical strength check , metallurgical test , hardness test , the fracture electron microscopy scan test analysis . The results show that the pawl punching punch Cr12MoV cold work die steel , carbide structure zonal distribution and low hardness , and ultimately lead to longitudinal cracking ; shaped chute board the punch selection of powder metallurgy steel S790, material and heat treatment method selection appropriate secondary cracks observed in the fracture to intergranular fracture, using scanning electron microscopy and microporous pattern , which concluded that punch as brittle fatigue fracture . Followed by comparative analysis of the structure of fine blanking punch its fixed , finite element analysis software to punch in the screw preload and punching force under the state of stress using ANSYS Workbench , punch roots threaded hole at stress concentration and proposed punch reasonable structure improvement program . Finally, analysis of the overall structure of the ratchet fine blanking die , the distribution of stress and strain of the mold . For semi - punching punch blade stress value is too big problem, to optimize thin Punches structure , and the optimized structure further analysis verified the results show that the the Punches maximum stress value is reduced by 40% .
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