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To further improve the polished quality of blades surface, a new polishing process-ultrasonic vibration assisted belt flapwheel flexible polishing (UBFP) is proposed in this paper. The trajectory state of abrasives and the continuous polishing process were analyzed, and the interlace phenomenon was described. The influences of main parameters on the quality of machined surface were discussed through experiments, and the prediction models of surface roughness(Ra and Rz) were established. The results showed that lower surface roughness and less polishing marks could be achieved by UBFP, and the models were reliable that can be used in further processing and research. This study can be considered as a theoretical and experimental reference to advancing the polishing surface quality of the blisk blade.

The objective of this study was to evaluate the usefulness of T2 high signal intensity (T2-HSI) and decreased anteroposterior diameter (APD), diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) in evaluating postoperative cervical cord function.

Gamma titanium aluminide alloys (γ-TiAl) are widely recognized as potential replacement for nickel-based superalloys in aerospace. However, along with brittleness at room temperature, poor surface quality and sever tool wear undermine their machinability, so that γ-TiAl alloy is considered as a typical intractable material. Tool selection and geometry optimization are encouraging strategies to improve the machinability of this kind of material. In this work, the cutting performance of six carbide grade tools is compared. And the cutting force, surface roughness and tool wear are selected as the evaluation criterion for the tool material determination. Then, the effects of tool geometry parameters including rake angle, primary relief angle and helix angle on surface roughness and tool wear are further studied. The sample dataset is utilized to formulate the first-order model with interaction. The predicted results of these models accorded well with the measured results. Due to the multi-performance characteristics, grey relational analysis method is introduced into the optimization of tool geometry parameters. The analysis of variance is employed to identify the most significant factor. And then, the confirmation test showed the improvement of the multi-performance characteristics.