Study On The Preparation Of The Low Expansion Cordierite Ceramic Material Using The Desert Sand

In the current,many quality raw materials of ceramic are decreasing gradually,so it becomes more and more quickly to develop new materials to make high-quality ceramic,and it’s highly valued.For now,it has not been found that desert sand is applied to making low expansion cordierite ceramics.The innovation of this topic is using KuBuQi desert sand,magnesite and bauxite as main material to preparing low expansion cordierite ceramic materials.The topic optimizes the experimental formula by orthogonal and single factor test methods,and analyzing the test sample by the thermal expansion coefficient,the size of the water absorption and flexural strength,seeing the internal structure of test by XRD-ray diffraction and by electron microscopy SEM observation of the sample.To investigate the performance of samples from the composition of different formulations,the effects of different firing temperatures and different holding time and different time of ball milling.The analysis of every performance and XRD patterns of the tested samples show that:Different amount of sand has different influence on the synthesis of cordierite.Coefficient of thermal expansion of the sample decreases first and increases then,and it reaches least when the amount of sand is 50%.While the samples have better thermal expansion when the amount sand is 60%,it’s good for the application of sand.MgO in Magnesite is one of the main factors affecting the synthesis of cordierite.With the increasing of magnesite,thermal expansion coefficient of the sample increases first and decreases then,and the difference is larger.Thermal expansion coefficient reaches a minimum When the amount is 15%,indicating that too much or too little magnesite is negative to low thermal expansion coefficient.With the amount of bauxite increasing,the thermal expansion coefficient of the sample is gradually increasing,when the amount of bauxite is 30%,the thermal expansion coefficient is minimum,but the difference is less,excessive addition of bauxite is negative to reduce the thermal expansion coefficient.Firing temperature and holding time are also two major factors for cordierite synthesis,for the same starting material composition,with firing temperature rising,the amount of cordierite is also increasing,the thermal expansion coefficient decreasing,indicating that the higher temperature firing is helping for cordierite synthesis;holding time also have some effect on the thermal expansion coefficient,the starting material and firing temperature is same,when the holding time is between 0 and 60min,with the holding time increasing,the thermal expansion coefficient of the sample decreases,it reaches a minimum of 3.00×10-6/℃,when the holding time is 60min,while the holding time lengthens to 90min,the thermal expansion coefficient of the sample increases.Experimental tests show that Selecting the appropriate incubation time temperature is more favorable than increasing firing temperature.This experiment obtained the minimum thermal expansion coefficient ceramic material as 3.00 × 10-6/℃ at 1300℃,for 60min.Milling time has a little influence on the thermal expansion coefficient of the sample,so I chose the milling time was 30min,it can mix raw material adequately.Desert sand is used in this study as the main material,due to a rich source of Aeolian sand,it will be used extensively for the huge demand for materials of ceramic production.so it helps to make full use of waste resources,and it has important strategic significance in preventing sand,controlling sand and using sand.While using this synthetic method for preparing the material has a broadly valuable application that with a low coefficient of expansion,excellent thermal shock resistance properties.