Figure 4
From: Densification in transparent SiO2 glasses prepared by spark plasma sintering
TEM observation of SPS-SiO2 glasses. TEM images of the (a, c) surfaces and (b, d) insides of the SPS-SiO2 glasses prepared at 6 MPa, 1300 °C and 70 MPa, 1400 °C, respectively.
