Preparation, characterization and annealing behavior of nanostructured Al₂O₃ coating on quartz fiber by non-electrode plasma synthesis

In the present manuscript the patented non-electrode plasma electrolysis technique was successfully applied in order to deposit nano-structured Al₂O₃ ceramic coating on the quartz fiber. It was found that the grooves on the blank fiber were covered by Al₂O₃, accordingly decreasing the surface defects. In this case, the coating effectively improved the breaking strength of the quartz fiber at elevated temperatures. The coated fiber still exhibited relatively higher strength of 0.38 N/tex after annealing at 600 °C for 60 min, nearly three times as that of the blank fiber. Both the formation mechanism and the protection mechanism of the Al₂O₃ coating were systematically investigated. We believe that the non-electrode plasma electrolysis will find a wide range of applications in the surface modification of non-conductive fibers.