Rake angle measurement of inclined slotting cutter
This paper analyses the blade shape, the parameters of rake angle of slotting cutter. The theoretical analysis process of a novel rake angle error measurement is introduced, which is built on the theory that the rake face of the inclined slotting cutter is a flat surface. For the systematic errors is caused by inaccurate measurement, the paper give in-depth analysis in various situation. By testing in the GD40-type CNC Gear Measurement Center, the accuracy testing results validate the correctness of the method.
Notice of Retraction3D probe radius compensation in measurement of characterized curves of complex helicoidal surface
Probe radius bias processing is a key technology in CNC measuring center. Based on the principal that the trace of the center of the probe is the offset surface of the measured helicoidal surface, a theoretical model is established for describing the trace surface. And three-dimensional probe radius compensation is proposed. Finally, the measuring example is given. The result shows that the three-dimensional probe compensation is accurate and convenient to measuring characterized curves of complex helicoidal surface.
EFFECT OF SAMPLE PREPARATION ON WATER TREE RESISTANCE OF XLPE/SEBS BLENDS
The effects of an aromatic polymer, such as poly[styrene-b-(ethylene-co-butylene)b-styrene] (SEBS), and its preparation processes on water tree resistance, morphology, crystallinity, dielectric constant and dielectric loss tangent of crosslinked polyethylene (XLPE)/SEBS and XLPE/SEBS/ethylene vinyl acetate (EVA) blends were investigated. The XLPE/SEBS samples were characterized by means of differential scanning calorimetry, scanning electron microscopy, dielectric spectral analysis and the accelerated water treeing experiment. The results clearly showed that although SEBS was partially compatible with LDPE and it was dispersed evenly in XLPE matrix, the blends demonstrated excellent dielectric performances, such as dielectric constant and dissipation factor. The crystallinity of XLPE/SEBS blends was decreased with increase in SEBS content and it was further decreased with the addition of EVA. SEBS could effectively improve the water-tree resistance of XLPE and both SEBS and EVA were found to improve the water tree resistance of XLPE synergistically as expected. The differences in sample preparation processes could change the phase morphology and dielectric performance of the blends, and could also influence the dispersion of SEBS in XLPE matrix as well as the crystallinity of the blends. Different preparation processes led to different water tree resistance behaviours of the samples. The improvement of SEBS dispersion in XLPE matrix helped to improve the water tree resistance of XLPE.