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Porous copper fiber-sintered sheets (PCFSSs) with different porosities were fabricated through the solid-phase sintering method using cutting copper fibers. PCFSSs with the same porosity and different porosities were then joined via a fluxless soldering method. By analyzing the uniaxial tensile property of the PCFSSs, the formation mechanism of the soldered PCFSSs was investigated. The difference in the tensile properties between the soldered and original PCFSSs was examined. Experimental results indicated that, for the PCFSSs with homogeneous porosity, reducing the porosity increased the tensile strength and elongation at break significantly. The fluxless soldering method with the lead-free solder resulted in excellent joining of the PCFSSs with the same porosity and different porosities. Moreover, the final tensile strength of the soldered PCFSSs with the same porosity was nearly equal to that of their parent PCFSSs. The tensile strength of the soldered PCFSSs with different porosities depended on the higher-porosity section. After soldering the PCFSSs, Young’s modulus increased and the elongation at break reduced.

To mass production of metal fibers with rough surface, a new type of multi-tooth tool and a special device were developed for fabrication process of metal fiber using continuous feeding of copper wire. A cutting model of multi-tooth tool was established. Whereafter, its cutting mechanism was discussed and analyzed by using a finite element method (FEM). The equivalent diameter and surface morphology of copper fiber which - were affected by processing parameters was investigated. Based on both experimental and simulation results, it is found that several fine tooth contacted with the copper wire could participate in the cutting process with continuous feeding of copper wire, a number of long copper fibers could be produced. Thus the processing efficiency of copper fiber with rough surface was greatly improved. In addition, the tool installation angle exhibited an influence on the equivalent diameter and surface morphology of copper fiber. Comparing with the feed rate, the equivalent diameter of copper fiber was remarkably affected by the cutting depth. However, these two parameters ha-d little effect on the surface morphology of copper fiber. Thus, the long copper fiber with rough surface could be fabricated under the condition of tool installation angle of 20–45°, wire feed rate of 0.42–0.72 m/s and cutting depth of 0.15–0.30 mm.