The effects of slag prticle size, $Na_2SO_4$ addition and sulphide in slag to the foam formation was investigated. This investigation showed that the slag particle size and the amount of $Na_2O$ had produced effects on the size of the foam, foam distribution and firing temperatures. In addition to that the amount of sulphide loss during the firing was controlling factor for the foam formation. The smaller slag particles and higher firing temperatures increased the loss of sulphide in the slag. The addition of $Na_2SO_4$ in the slag batch was likely to inhibit the foam formation. The larger slag particles resutled in the larger foam size and tended to be increasing the batch firing temperature. The main constituents of slag formed glass consisted of wallstonite and glassy phase. It is believed that the controlling the slag particle size and the amount of $Na_2SO_4$ in the slag batch will probably be main factors in foam formation.

Test-bricks were prepared from an artifically graded Ham Kang sand and a commercial CaO and autoclaved for 6 hours at $16 kg/cm^2$ pressure $(203^{\circ}C)$. Bricks were tested for compressive strength, free lime, saluble silica and amount of water absorption. Physical properties of bricks were very much depended on the size distribution of sand particle and the amount of soluble silica in bricks.

In the present investigation, refined alumina obtained from alunite locally available was used as a aluminous source to synthesize monocalcium aluminate $(CA)_3$ the major mineral constituent of alumina cement. The influence of $SiO_2$ and $Fe_2O_3$ contents on the formation of monocalcium aluminate was studied by X-ray diffraction analysis mainly. About 0.8-1.0 of $Al_2O_3/C_3O$ mol ratio and less than 4 percent of $SiO_2$ were desirable for the effective formation of CA. The small amount of alkali and sulphur contents contained in refined alumina from alunite as the impurities were affected to form $C_4A_3S$ and $C_3S_2$, disadvantageous compounds for the alumina cement, therefore the impurities should be restricted in minimum content as possible.

The hydration reaction of the slag-gypsum system was studied by X-ray diffraction, differential thermal analysis, optical icroscopic observation, and measurement of heat liberation of hydration. 1. Domestic granulated slag was almost noncrystalized state, and its mineral compositions calculated were 46.53% of gehlenite, 28.14% of akermanite, and 19.04% of wollastonite. 2. The slag quenched with water at relatively high temperature had better reactivity. 3. The production of ettringite, CSH gel and AH3 gel were stimulated by effect of $Ca(OH)_2$, $Mg(OH)_2$ and calcined dolomite as activators, and the strength of hardened body would be developed by forming compacted microstructure.

The purpsoe of this study was to produce domestic stamping materials; sling mass which could be used as unburned refractory for iron melt'ladle. Batch compositions were based on Belgian Ladelite; mineral compositions were composed of 84 wt% of quartz and 16 wt% of clay, and particle sizes were divided into 12 wt% of 1410/297㎛, 18wt% 297/149㎛, 20wt% of 149/74㎛, 11wt% 74/44㎛ and 39wt% 44㎛ under. The effect of variable batch compositions were also investigated such as substitution of pyrophylite or industrial grade alumina for quartz and of zircon for portion of quartz and clay, increase of clay and addition on sericite. Samples were pressed at 100kg/㎠ with 7.4wt% of water or 7.4wt% of 4 wt% PVA solution. Dried and Fired properties of samples such as linear shrinkage, apparent porosity, modulus of rupture, refractoriness and corrosion resistance to blast furnace slag were investigated. The results are summarized as follows. 1. Dried samples are shrinked, but fired at 700-1400℃ expanded. Samples fired at 700-1000℃ and 1200-1400℃ tended to expand with incresing of firing temperature, but fired at 1000-1200℃ tended to shrink with increase of firing temperature. 2. Apparent porosity of samples fired at 700℃ is increased, but fired at 1200-1400℃ decreased with increasing of firing temperature. 3. Modulus of rupture of samples fired at 700℃ is decreased, but fired at above 700℃ increased with increasment of firing temperature. 4. Dried samples with 7.4 wt% of 4 wt% PVA solution better improve modulus of rupture than with 7.4 wt% of water, but the firing strength of the sampels fired at 700-1000℃ is showed reversely. 5. In quartz-clay system, mineral phases of samples fired at above 1200℃ are consisted of α-quartz, α-cristobalite and mullite. Respectively as firing temperature was rising up, intensity of α-cristobalite and mullite is in creased. 6. Quartz-Kibushi clay system, Kimcheun quartz(substitutuion of portion of industrial grade alumina for quartz) Hampyeung clay system and pyrophyllite-clay system are better in corrosion resistance to blast furnace slag than burned pyrophyllite brick. 7. 84 wt% of pyrophyllite-16wt% of clay system is superior in modulus of rupture and corrosion resistance to blast furnace slag to 84 wt% of quartz-16 wt% of clay system.