The quartz glasses were prepared by fumed silica powders sintering method at , , in air and the effect of sintering temperature on their properties were investigated. The X-ray diffraction pattern, the OH concentration, the light transmittance, the apparent porosity and the density were analyzed. The transparent quartz glass were obtained above . The OH-group and macroscopic pores were removed above and highest density and light transmittance were obtained at .
The quartz glasses were prepared by sintering of fumed silica powders and the effect of OH concentration on their surface on sintering was studied. Through the firing process, the fumed silica was crystallized from 1180 to region. The amount of hydroxyl group decreased with increase in calcination temperature and consequently the crystallization was prevented. A transparent quartz glass was obtained from fumed silica, previously calcined at , by the sintering at for 1 h.
Fe based (FeCSiBPCrMoAl) amorphous powder, which is a composition of iron blast cast slag, were produced by a gas atomization process, and sequently mixed with ductile Cu powder by a mechanical ball milling process. The Fe-based amorphous powders and the Fe-Cu composite powders were compacted by a spark plasma sintering (SPS) process. Densification of the Fe amorphous-Cu composited powders by spark plasma sintering of was occurred through a plastic deformation of the each amorphous powder and Cu phase. The SPS samples milled by AGO-2 under 500 rpm had the best homogeneity of Cu phase and showed the smallest Cu pool size. Micro-Vickers hardness of the as-SPSed specimens was changed with the milling processes.
Fe based (FeCSiBPCrMoAl) amorphous powder, which is a composition of iron blast cast slag, were produced by a gas atomization process, and sequently mixed with ductile Cu powder by a mechanical ball milling process. The experiment results show that the as-prepared Fe amorphous powders less than 90 m in size has a fully amorphous phase and its weight fraction was about 73.7%. The as-atomized amorphous Fe powders had a complete spherical shape with very clean surface. Differential scanning calorimetric results of the as-atomized Fe powders less than 90 m showed that the glass transition, T, onset crystallization, T, and super-cooled liquid range T=T-T were 512, 548 and 36, respectively. Fe amorphous powders were mixed and deformed well with 10 wt.% Cu by using AGO-2 high energy ball mill under 500 rpm.