An Investigation of the formation of the lone biscui recipe for the application of both mat and transparent glazes

In this study, one recipe of wall tile for the both application of mat and transparent glazewere investigated. Although there was not to be observed that dismatch between glaze andbody for high expansion glaze, their biscuit strengths were found to be low. In case of highexpansion glaze applied to low expansion body, it was observed that dismatch between glazeand body. This disadvantage coming from different expansion characteristics of glaze and bodycan effect working time and labour efficiency and production cost in negative manner. Thecurrent study was done in five stages.At the beginning, over the body which has lower expansion than glaze, body strengthswere tried to be increased. For this aim, clay level was increased between 5-15 wt % and quartzlevel was decreased between 45-63 wt %. In prepared four recipes, the highest strength valuewas found 159 kgf/cm2. Due to this value is far from the standard biscuit strength value(212 kgf/cm2), this stage did not give a positive result.According to the result of mineralogic and X-ray diffraction (XRD) analysis done forBAZ 1and BAZ 2, SiO2 amount was found to be decreased in BAZ 1 more than in BAZ 2. As aresult of this, it was estimated that plagioclase in the body contains more Na than Ca. After thisstage, second and third stages were studied.At the second stage; 5 wt %, 10 wt % and 15 wt % quartz sand were added into recipeto decrease thermal expansion of BAZ 1 recipe. By increasing quartz in the recipe totalshrinkage values were found 0.44 %, 0.47 % and 0.47 % respectively, green body strengthswere found to be 16.6, 12,1 and 12.78 kgf/cm2 respectively. Biscuit strengths were found to be202.25, 198.9 and 210 kgf/cm2 respectively. And lately, water absorptions were found to be1.25, 16.56 and 16.83 % respectively. The produced tile specimen were glazed by mat glaze andthis showed cracks at 205ºC.viiAt third stage; 5, 10 and 15 wt % raw albite were added into BAZ 1 recipe. By rate ofincreasing albite in the recipe, total shrinkages were found to be 0.44, 0.47 and 0.39 %respectively. Green body strengths were found to be 14.33, 14.83 and 10.3 kgf/cm2 respectively.Biscuit strengths were found to be 180.20, 182.32 and 177.32 kgf/cm2 respectively. And finallywater absorptions were found to be 16.83, 18.49 and 16.79 % respectively. Tiles glazed withmat glaze consist of 5 wt % and 10 wt % albite showed cracks at 175° C. At around 15 % albitecontained mat glaze was cracked at 205° C.At the fourth stage; the best fitted mole ratios of each oxides were tried. Three differentoxide groups were searched in this stage. These are CaO-MgO, NaO-SiO2, and Al2O3-K2O. Thehighest strength value in these group was found 248.88 kgf/cm2 at these strength value totalshrinkage was found 0.94 %, green body strength 9.52 kgf/cm2 and water absorptions wasdeterminated 16.74 %. These tiles were glazed by mat glaze and cracked at 155ºC.At the last stage; 7 % and 10.5 % Bilecik Osmaneli K 4 clay which contains of highamount of calcium, was added. For DOM 20 recipe which has the best psycho mechanicalproperties, it was found that total shrinkage was 0.50 % green body strength, 14.12 kgf/cm2 andbiscuit strength 240.16 kgf/cm2 according to wall tile standard for TSE EN 159, a tile mustresist 200° C. The produced tiles with glazed by mat DOM 20 did not crack at 200 ° C.Consequently, it was searched to make appropriate recipes according to TSE EN 159and factory standard by using raw materials at different stages. But there were not anyacceptable values according to references. Bilecik Osmaneli clay added recipe showed suitableresults according to TSE EN 159 and factory standard. This recipe was decided to try factoryconditions and to use directly.In addition with trade calculation the usage of this recipe in factory condition will lowerannual total cost of the tile production about 17.000 YTL.Key Words : Glaze-body fitness, recipe, thermal expansion, wall tile.