The Effect of the Mullite Phase on Some Properties of Hard Porcelain

In this study, hard porcelain (with different ratio of mullite phase) has been perpetrated this type of traditional ceramic uses in much different applications because of their properties like chemical stability and high hardness and electrical resistivity. Conventional ceramic techniques (The powder technology) were used to fabricate this type of ceramic because of its low cost and mass production uses as compared with other techniques. Four mixtures from hard porcelain has been used from present available raw materials (flint ,clay mineral and flux) , the mullite phase state and calculated by using X-Ray diffraction techniques, sample tested at different sintering temperatures. The effect of increasing of mullite phase on properties like density, porosity, hardness and M.O.R (Modules of rapture) were studied. From this study has been shown the increasing of mullite phase lead to increasing density ,hardness , M.O.R and decreasing the porosity because of exist of mullite phase in ceramic matrix