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The mechanical part was heated to the heat treatment temperature, and the surface color changed with temperature. The infrared radiation thermometer was used to get heating part temperature, and the corresponding color images were taken by the camera at the same time. The program was designed to analyze the images and display the temperature. To decrease the effect of the noise disturbance in the process of image, the combined filter method was used. The relationship between the temperature and image of heating mechanical parts were obtained through digital regression. The analysis and comparison results show that the temperature measurement precision of three primary color is higher than gray’s from 700°C to 1100°C. The three primary colors have more information for image recognition than that of gray image, and are suitable for higher technical requirements.

In order to study viscoelastic properties of asphalt mixture, an advanced Shear Rheometer is used. The continuous dynamic frequency scanning test is carried out, which can get full-temperature-full-frequency master curve of asphalt mixture by the time-temperature equivalence principle. The CAM model acts as the rheological model for studying viscoelastic properties of asphalt mixture, because CAM model’s parameters have clear physical meaning. Then viscoelastic properties of asphalt mixture are studied basing on the four equations of CAM model in the full-temperature-full-frequency range.

The effects of vanadium microalloying on the hardness and its distribution of alloy ZG270-500 smelted in intermediate frequency induction furnace were studied. Vanadium microalloying increased the hardness of test alloys effectively. By scanning electron microscope (SEM) and energy disperse spectroscope (EDS) analysis, it was found that VC was the powerful heterogeneous nuclei, which prompted numerous nucleating, refined the structure grains and caused the serious crystallographic lattice distortion, so the hardness increased. Proper content of vanadium prompted more even hardness distribution across the whole temperature front section. However, overdoes vanadium microalloying easily caused mass oxides of V2O3, which kept solid phases with high meting point in metal liquid to increase the viscosity and decrease the fluidity of metal liquid, resulting in inadequate metal liquid feeding, serious structure shrinkage porosity in center and worse hardness distribution along the different isotherm fields. 0.16wt.% vanadium microalloying brought the optimal hardness uniformity among test alloys with the approximate 1 hardness ratio R between the center and the margin.