Research On The Physic And Mechanic Properties In The Surface Of Closed Extruding Fine-blanking Works

The section of fine-blanking parts has good finish, verticality, planeness and high precision. Using precision fine-blanking process instead of cutting process to make the precision profile parts of disk shape, that the efficiency is dozen times than traditional machining, and greatly reduce the production cost. Closed extruding fine-blanking is a kind of brand-new fine-blanking forming process, which can achieve fine-blanking processing of low plastic and thick plate; it is an important supplement of common fine-blanking process. Closed extruding fine-blanking process has the characteristics of high processing speed, high strain degree and high deformation pressure, the processed materials deformation area mainly focus on the both sides of the punch and die's cutting edge, where the materials'microstructure and performance will change a lot in the process. 2A12 is a material that has low fine-blanking performance, this article use closed extruding fine-blanking method to processing it, observe the surface microstructure of work-piece before and after the deformation and test the properties of materials' processed surface, then combine these two aspects of the results and analysis wear failure mechanism under the condition. In order to compare to the effect of common turning and grinding process, we set the turning parts as contrast experiment. Through the results to reveal the alternate mechanism of microstructure and properties of closed extruding fine blanking process, this will promote the mercerization of the advanced technology.This topic firstly prepared specimens by closed extruding fine-blanking process, and then adopts microstructure observation, scanning electron microscope microstructure observation, EDS object energy spectrum analysis and X-ray residual stress measuring, polarization curve analysis, metal materials reciprocating friction and wear test and other analysis methods to analysis microstructure and properties of the closed extruding fine-blanking work piece, and compared to the work piece processed with the lathe work.On the basis of the experiment, we discussed the friction and wear mechanism of the surface about the work piece, and reached the following conclusions: the roughness, organizational change, inclusion refinement, work hardening effect, the surface residual compressive stress of the surface will increase the wear resistance of the work piece, However, grain growth, hardness distribution and the uneven distribution of surface residual stress, such as long-term decline in corrosion resistance will make the wear resistance decline of the work piece. Friction and wear experimental results showed that the factors improved wear resistance of the material dominates significantly in the process and the wear resistance of the work piece improved obviously.Through the research of this project to prove that: the closed extruding fine blanking processing methods, can improve the surface organization structure of the work piece greatly, and the life of the work piece is also greatly improved.