Study On Ultrasonic Pulse Electroforming And The Properties Of Copper Matrix Carbon Fiber Powder Composite

Carbon fiber powder is a kind of high strength, abrasion resistant and corrosion resistant material, which is made by carbon fiber filament through special surface treatment and grinding. For its weeny shape, pure surface and large specific surface area, it has been a kind of good performance composite filler. Copper matrix carbon fiber powder composite is prepared by composite electroforming technology with ultrasonic and pulse current, and the exploration and research on preparation process and properties of the composite electroforming layer are carried on.Surface modification of carbon fiber powder is studied. The surface of carbon fiber powder is coarsened by ball- milling, which can avoid structure destruction and intensity reduction of the carbon fiber po wder. For reducing the surface tension of carbon fiber powder, the thesis puts contact angle of the carbon fiber po wder as test index to study three kinds o f surface active agent. Finally, 125 mg/L of sodium dodecyl sulfate is selected as the additive.The movement of carbon fiber powder in the electroforming solution is affected severely by the electroforming flo w. In order to make carbon fiber powder deposit uniformly in the composite electroforming layer, electroforming solution flow field is simulated using the FLUENT module of ANSYS soft ware, and combines with experimental verification. When the electrode is relative to the electrolyser long edge direction at 75° in the square electrolyser and the stirring speed of stirrer is 60 rad/s, carbon fiber powder can be high content and uniform distribution relatively within the composite electroforming layer.Five experimental parameters are focused on analysis t he effects on the carbon fiber powder content(C_LP), micro-topography, micro-hardness, abrasion resistance and conductivity of the composite electroforming layer. The five experimental parameters are the carbon fiber powder addition in electroforming solution（CA）, pulse on-times, pulse off-times, pulse peak current density and ultrasonic po wer. Research results show that the process parameters affect the performance of the composite electroforming layer mainly by changing the C_LP. Carbon fiber powder in the composite electroforming layer can refine the organization of the composite electroforming layers, the higher the content, the lower the material smoothness, the greater the porosity, the lower the tissue density; The higher the C_LP, the lower the microhardness of the composite electroforming layer; The abrasive resistance of composite electroforming layer is enhanced; The electroforming layer keeps high conductivity.Technological parameters are optimized using orthogonal experiment. When the pulse on-times, off-times, peak current density, ultrasonic po wer and C_A is 200 μs, 400 μs, 30 A/dm², 90 W and 15 g/L respectively, the composite electroforming layer presents better abrasion resistance and conductivity. The friction coefficient, the abrasion loss, the resistivity and the micro- hardness of composite electroforming layer is 0.228, 0.0094 mm³, 0.0224 mΩ/mm and 133.5 HV respectively.