Quality Control And Staircase Effect Reduction Of 3D Micro Electrode

Recently, With the rapid development of microelectronics, precision machinery, bio-medical, aerospace and other industries, the demand for micro-parts industry is growing. Size of miniature parts small, lightweight, and therefore difficult to use conventional machining methods for producing molded. Micro-EDM is a micro-processing technology, the technology can process a variety of super-hard, brittle materials, and in the process of macro cutting force is small. Therefore, very suitable for the preparation of Micro-EDM miniature parts. In Micro-EDM by micro columnar electrodes on the workpiece material layer by layer scanning EDM obtain higher precision micro-structure, however, there is a low processing efficiency, electrode wear large and complex motion control feed disadvantages to this method. The three-dimensional stack of microelectrodes used in Micro-EDM can effectively solve the above problems, a three-dimensional stack microelectrode is based on a layered object manufacturing process, including line cutting station and the vacuum pressure thermal diffusion welding station, line cutting for cutting copper foil to obtain a two-dimensional micro structure having a specific structure, thermal vacuum pressure diffusion bonding the multilayer structure of two-dimensional micro-welding according to a certain order in order to fit the laminated 3D microelectrode. When a three-dimensional stack containing microelectrodes ramp structure and surface preparation, it will inevitably appear staircase effect. To solve this problem, the dissertation made a major study, the main work and conclusions can be classified as follows:(1) In order to eliminate a three-dimensional laminated seams discharge marks microelectrodes of pure copper produced in the spark discharge obtained microcavity generated, based on Micro-DLOM plated copper foil as the material in the process for preparing a three-dimensional laminate microelectrode. Detailed study of the tin film thickness, affect the thermal diffusion bonding temperature, thermal diffusion bonding time for micro-cavity surface after the discharge of the discharge marks. Studies have shown that: three-dimensional composite microelectrodes connected in a tin film thickness is 1 ?m(thickness of 50 ?m), the thermal diffusion welding temperature of 900?, the thermal diffusion welding time was 15 h, under the pressure of 0.127 MPa parameters obtained reliable, with good EDM performance, will be applied to Micro-EDM, the results of the joint surface discharge machining marks disappeared.(2) Staircase effect is the principle of the laminate manufacturing error. Through analysis, the layer thickness is one of the important factors affecting the level of effect, layer thickness greater the effect of the more obvious steps. Select the direction of stratification is also one of the important factors in the effect of the step, choose the right direction layered laminate can effectively improve the precision of manufacture.(3) When tin-plated copper foil laminated to the preparation of material containing three-dimensional microelectrode ramp structure, the pressure in the vacuum thermal diffusion welding process, under pressure, the molten copper tin compounds raise the sheet between adjacent cells step gap, can effectively eliminate the step effect.(4) By three-dimensional CAD software to design the structure of the hemisphere containing microelectrodes, after a two-dimensional layered structure is calculated for each unit size sheets. Pure copper and tin foil laminate of two materials prepared three microelectrodes and applied Micro-EDM. Experimental results show that the electric discharge machining can obtain higher precision micro-cavity surface of the cavity through the same queue electrode...