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In order to monitor the process of laser remanufacturing and control the quality of remanufacturing, a monitoring and control system for laser remanufacturing was constructed with its hardware and software. The schedule of the system including signal condition, software interface, sampling and control method, was introduced. Infra-red thermometer with dynamic aiming device was designed to track the molten pool location. Photoelectric sensor was developed to measure the flow of powder. The contrast test results show that the fuzzy PID control system for powder feeding could achieve stable flow.

In order to study the influences of aggregate size on CO2laser absorption property, several special absorbing coatings were prepared from four kinds of different particle sizes (45 μm, 13 μm, 6.5 μm and 1.6 μm) TiO2powder. The CO2laser absorption capacities of these coatings were studied by comparative analysis of the surface morphology and laser heated areas. The results show that the absorbing capacity increases with particle size dwindling. In all samples, the 1.6 μm specimens display the best performance with the largest laser heated area on cross section. The analysis indicate that, the decreasing of particle size will lead to an increase on absorbing surfaces, which is benefit for improving the absorbing capacity. Furthermore, smaller size particles also can cause the temperature increased faster than large particles, which lead to a further increase on absorbing performance for the positive feedback effects between the temperature and the absorbing capacity. Finally, the effects of particle size variety on designing absorbing coatings are also discussed.

Featured by cheap equipment, easy operation, nice controllability and low consumption, compound electroless deposit becomes an effective method to avoid failures such as high-temperature corrosion, fatigue and abrasion. Combined with the merits of nanometer material and laser treatment technology, the Ni-P nanometer Al2O3 electroless deposit after laser strengthening can get finer grains with high performances. This paper researched the technique of laser strengthening on 3Cr13 stainless steel after Ni-P-nano Al2O3 electroless plating. The experiments with low laser power and high laser power were performed. The crystallinity, phases and element distribution of coating were analyzed by X-ray Diffraction (XRD) and energy spectrometer (EDS). The microhardness and wear resistance of coating were measured as well. The results showed that composite coating heated by low laser power leads to transformation from non-crystal to crystal with high hardness. When heated by high laser power, the electroless deposit layer melted, and most of amorphous transformed to crystal. Combined with high laser power and high scanning velocity, the electroless deposit with finer grains and excellent properties was obtained. The strengthening mechanism was analyzed, and the properties including hardening and wear resistance were investigated as well.

This article discusses the influence factors of bilingual teaching effect by bilingual teaching practice of the Advanced Manufacturing Technology, and proposes solutions. Practice shows that the reform of teaching idea is the prerequisite for the effective bilingual teaching, and PBL teaching model is the effect ways to improve the effects of bilingual teaching.