Investigation of compressibility and Foaming behavior of steel slag /waste glass composites by changing particle size distribution

In the present investigation, the foam like composites, fabricated by window glass (50 wt-%), steel slag (50wt-%) and different foaming agents (carbonates, carbon, SiC) were considered by press–sintering method (50-100 MPa pressing pressure and 1200ºC sintering temperature). The effect of particle size distribution (different ranges from 45μm to 150μm) on green and fired density of resulting glass-ceramics was evaluated. Six mixes of different particle size distribution for slag powder and slag/glass powders were designated. It was shown that by using medium fine grade of the slag powder (average particle size under 100-120 μm), the compaction and the green densities of samples were 16% increased while in the case of slag/glass composites due to the high hardness of glass powder, the compaction of composite was 11% increased. For finer distributions (average particle size 50-70 μm) the compressibility has decreased rather than medium samples because of short range of distribution. That was in the opposite in case of fired density of different particle sizes. It was observed that using finer particle sizes in the case of CaCO3 foaming agent, the density varied from 0.80 gr/cm3 to 0.43 gr/cm3 while in the case of SiC it changes from 0.80 to 0.51. probably in the case CaCO3 as foaming agent faster coalescence process and gases trapping from decomposition has been occurred.