A series of zeolite-derived silica glasses have been fabricated through the order-disorder transition process of zeolites using spark plasma sintering (SPS). The samples were characterized by UV-VIS-NIR transmittance, Raman spectra and Vicker’s hardness. Results showed that the transmittance of zeolite-derived silica glass samples increased with the sintering temperature increasing. The transmittance of the sample prepared at 1300°C was lower than 5%. The highly transparent samples could be obtained when the sintering temperature was above 1350°C. The transmittance of these samples was higher than 80% in the range of 780~1700nm and 60% in the UV-vis range of 250~780nm. One absorption band at 300nm can also be observed in the spectrum. The reason of this phenomenon could be ascribed to a few left crystallite fragments of ZSM-5. The Raman spectra showed that the bands at 378 and 292cm-1of ZSM-5 were significantly weakened and then disappeared with increasing the sintering temperature and the bands at 489 and 600cm-1 of silica glass became more apparent. The Raman spectra of the samples obtained above 1350°C were the same as that of the fused silica glass. The Vicker’s hardness of as-prepared samples increased with the rising of the sintering temperature. The maximum hardness of 7.31 GPa was achieved for the sample sintered at 1400°C. The fracture toughness of samples increased from 0.83 MPa·m1/2 to 2.37 MPa·m1/2 with the sintering temperature increasing.
Rapid manufacturing of silica glass parts with complex structures through stereolithography and pressureless spark plasma sintering
