| Because of their excellent electrical,thermal conductivity and other properties, short carbon fiber reinforced Cu-based composites are widely used in the field of spaceflight, aviation, machine, electron, chemical industry, etc. Nowadays, powder metallurgy is a common-used method for acquiring the C/Cu composite. However, the homogeneity between the SCFs and Cu matrix is bad,which will cause the overall properties of the composites bad, restricting the short carbon fiber reinforced Cu-based composites further growth. A new method of pretreatment was used to make the SCFs/Cu composite filament. Then, powder metallurgy method was used to make the short carbon fiber reinforced Cu-based composites. Besides, we get the relationship between the surface oxygenic functional groups and the calcinations temperature, one of the most important parameters of air oxidation process. From the experimental result, optimum technology was acquired. In the end, we try to discuss the mechanism of the electro-copper plating from the perspectives of applied voltage and surface oxygenic functional groups respectively.Electro-less plating and electro plating are the wildly used methods. The electro-less copper plating with formaldehyde as reducing agent is a common method. However, because the reducing agent is a kind of toxic substance, this method is not environmentally friendly and unhealthy. We use the electro-less copper plating with sodium hypophosphite as reducing method to acquire the C/Cu composite wires, which are both environmental protection and healthy. In addition, the relationship between microstructure and properties, such as density, electrical conductivity, thermal conductivity, thermal expansivity and the HV value, is analyzed. Results were as follows: the electrical conductivity along the axis of the SCFs can reach 85% of the pure Cu, when 10.2% of the composites are the SCFs; Thermal conductivity is the best along the axis when 10.2% of the composites are the SCFs. The values are 47.9 W/m K at 30oC,67.9 W/m K at 200oC, respectively. In regard to the thermal expansivity, the best value appears when 30% of the composites are the SCFs. And the specific values are 13.9×10-6/K from 30oC to 100oC, 15.2×10-6/K from 30oC to 200oC. HV value can reach 121HV when the percent by volume of the SCFs is 30%.Carbon fibers untreated are surface inactive, low surface energy, and less oxygen functional groups. So, it will restrict the development of the composites because of the poor fiber/Cu interfacial adhension. We expect to make the SCFs metal-coated surface in the condition of the most oxygen functional groups both of adopting electroplating and electro-less plating method. Electrochemical oxidation is a commonly used method in daily industrial production. However, the follow-on work is cockamamie as well as inefficient while the air oxidation process is so convenient that we choose it as the method of surface treatment of SCFs. In this paper, we find the relationship between the calcining temperature and the quantity of the surface oxygenic functional groups. The XPS and FTIR show that there are the most oxygen-containing active function group, such as–OH and -C=O, when the calcining temperature is 400oC. In addition, we find that the driving forces of the reaction of the electro-plating are the applied voltage and the surface oxygenic functional groups. When the applied voltage is too low to promote the common reaction, only the positions which pocess the surface oxygenic functional groups can be deposited copper. This means that the surface oxygenic functional groups can lower the electrode potential of the carbon fibers. Then, the surface oxygenic functional groups will be weakened as the applied voltage is increased big enough to get the smooth Cu coating.
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