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Computer vision inspection system is often applied in automatic wire bonding to ensure the location accuracy and speed, while feature selection affects the performance of inspection system. In this paper, a new feature extraction and matching location algorithm based on SIFT-MIC is proposed for wire bonding. The algorithm chooses MIC corners in the neighborhood of SIFT feature points to increase the robustness of feature extraction. Meanwhile, the selection of SIFT- MIC feature points is before the generation of SIFT descriptors, to reduce the computation and improve the efficiency of feature extraction. The vector angle method is chosen to finish the matching location of the eye-point images and images to be matched. Experimental results show that SIFT-MIC algorithm is invariant to translation and rotation, and has high performance in the positioning accuracy and detection efficiency. The proposed algorithm is suitable for MEMS wire bonding images with rich points and lines features.

Nano-SiO2 composite is plated on P20 substrate and then carried out by laser strengthening. The topography and performance of Nano composite plating and the laser strengthened layer are studied by SEM, EDX, and WM-2002 friction wear testing machine, respectively. After laser process, the polyhedral Nano-SiO2 particles are formed; the microcrack and the gap of cladding structure can be eliminated. Comparing with the composite plating, the microhardness and the anti-wear of the laser strengthened layer are improved significantly.

Uniform Ni-P-nano Al2O3 eletroless plating layer was produced on medium carbon steel, and scanned by high power continuous wave (CW) CO2 laser beam. Optical microscope (OM) and scanning electron microscopy (SEM) were used to observe the morphologies of the coating. X-ray diffraction (XRD) and X-ray energy dispersive spectroscopy (EDS) were employed to analyze the phase transformation and element compositions of the coating. The microhardness and abrasive resistance before and after laser processing were checked respectively. The whole coating was divided into four regions from surface to inner as laser strengthened region, transition zone, heat affected zone (HAZ) and substrate. The strengthened coating had good performances such as smooth surface, uniform components and refined microstructures. The phases in strengthened layer obviously changed from amorphous to crystalline and the main phase was Ni3P with some non-equilibrium phases. The reinforced particles, Al2O3, were homogeneously dispersed in grain boundary, which could improve the properties. The microhardness of strengthened region was about 3 times of substrate, and the abrasive resistance of which was also increased owing to the Al2O3 particles.Uniform Ni-P-nano Al2O3 eletroless plating layer was produced on medium carbon steel, and scanned by high power continuous wave (CW) CO2 laser beam. Optical microscope (OM) and scanning electron microscopy (SEM) were used to observe the morphologies of the coating. X-ray diffraction (XRD) and X-ray energy dispersive spectroscopy (EDS) were employed to analyze the phase transformation and element compositions of the coating. The microhardness and abrasive resistance before and after laser processing were checked respectively. The whole coating was divided into four regions from surface to inner as laser strengthened region, transition zone, heat affected zone (HAZ) and substrate. The strengthened coating had good performances such as smooth surface, uniform components and refined microstructures. The phases in strengthened layer obviously changed from amorphous to crystalline and the main phase was Ni3P with some non-equilibrium phases. The reinforced particles, Al2O3, were homogeneously dispersed in grain...