Atmospheric pressure plasma technology has been presented as an effective tool in relieving or removing subsurface damage induced by previous mechanical machining process. However, the surface morphology evolution and mechanism during removing the subsurface damage using atmospheric pressure plasma processing after grinding to remove the subdamage is rarely reported. In this research, this procedure is studied based on experiments and measurement. Even if some unique properties of atmospheric pressure plasma processing are observed, such as particle exposure. From the mechanical machining to atmospheric plasma blasting, the RPV value increase from 1.338 μm to 1.361 μm due to some singular deep cracks that are not fully healed or filled by the abrasives. Corresponding peak-tovalley and RMS roughness evolution is investigated as well. It is revealed that the atmospheric pressure plasma process may end up with a planar surface depending on the damage removing. Density of the damage has more significant effect on the roughness evolution than damage depth.
This paper reports the development of high volume fraction SiCP/Al composite-bismuthate glass multilayer films optics Au-mirror with high reflectivity in a wavelength range of 760 to 1000 nm. Multilayer films were fabricated using an radio frequency-magnetron sputtering deposition system. The measured reflectivity of Ta2O5/SiO2/Au/Cr metal plus dielectric films optics Au-mirror could reach up to ≥97%. Then, on the basis of experiments, a Φ75-mm high volume fraction SiCP/Al composite-bismuthate glass multilayer optical Au-mirror for a wavelength range of 760 to 1000 nm was manufactured. The tested results indicate that a peak-to-valley value of 0.854λ (λ=632.8 nm) was achieved on the Au-mirror surface, and the slope deviation error for the flat surface was lower than 0.153λ root mean square. The surface roughness of Ta2O5/SiO2/Au/Cr multilayer thin films was 1.30 nm (Ra).