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Cordierite Based Glass-Ceramic

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Cordierite Based Glass-Ceramic DEPARTMENT OF CERAMIC ENGINEERING NATIONAL INSTITUTE OF TECHNOLOGY ROURKELA .SYNTHESIS AND CHARACTERIZATION OF CORDIERITE BASED GLASS-CERAMIC SUBMITTED BY SOUMYA SOURAV PATRA (110CR0103) (Under the guidance of Prof. Arun Chowdhury) In the partial fulfillment of the requirements for the degree Of Bachelor of Technology 1 | P a g e NATIONAL INSTITUTE OF TECHNOLOGY ROURKELA CERTIFICATE This is to certify that the thesis entitled, “synthesis and characterization of cordierite based glass-ceramic.” submitted by Mr. Soumya Sourav Patra (Roll no - 110CR0103) in partial fulfillment of the requirements for the award of Bachelor of Technology Degree at Ceramic Engineering in National Institute of Technology, Rourkela is an authentic work carried out by him under my supervision and guidance. To the best of my knowledge, the matter embodied in the thesis has not been submitted to any other university / institute for the award of any Degree or Diploma. Prof. Arun Chowdhury Department of Ceramic Engineering National Institute of technology Rourkela-769008 2 | P a g e ACKNOWLEDGEMENT With deep respect, I avail this opportunity to express my gratitude to Prof. Arun Chowdhury Department of Ceramic Engineering, National Institute of Technology, Rourkela for his inspiration and guidance and valuable suggestion throughout this research work. His vast knowledge in the field of Science and Technology helped to enlighten me. It would have been impossible on my part to come out with this project report without him. I would like to thanks to the HOD, Ceramic Department and all other faculties for their support and valuable suggestions throughout this research project. I would also take this opportunity to express my gratitude to the non-teaching staff for their help and kind support at various stages of work. I am also thankful to the Research Scholar in the Department of Ceramic Engineering for helping out in labs and analysis. And lastly I am thankful to my parents and friends for their constant support. Soumya Sourav Patra Roll No - 110CR0103 3 | P a g e ABSTRACT Cordierite glass-ceramic sample were made using with rice husk ash as the source of silica. Three different nucleating agent were introduced in the base glass composition - TiO2, ZrO2, and ZrO2-TiO2 in (1:1) proportion by weight. After preparation of these cordierite based glass-ceramic phase evaluation was studied in the temperature range 1250 to 1350oC. XRD and electron microscopy were employed to characterize all heat treated specimens. Linear thermal expansion behavior of the glass-ceramic samples was studied with the help of dilatometer. For hardness testing Vickers’s method was adopted. 4 | P a g e CONTENTS Serial no Topic Page no 1. INTRODUCTION 10-13 2. LITERATURE REVIEW 14-19 3. OBJECTIVE 20-20 4. EXPERIMENTAL PROCEDURE 21-27 [4.1] Raw material required [4.2] Preparation of silica from rice husk [4.3] Preparation of zirconium dioxide (nucleating agent) [4.4] Flowchart for cordierite based glass-ceramic preparation [4.5] Batch preparation of cordierite based glass ceramic [4.6] Cordierite based glass-ceramic preparation 5 TESTING AND CHARACTERIZATION 28-31 [5.1] Chemical Analysis of rice husk ash silica by Hf method [5.2] Bulk density and apparent porosity of cordierite based glass-ceramic [5.3] Phase analysis by XRD [5.4] Microstructure analysis by SEM [5.5] Measurement of linear thermal expansion coefficient [5.6] Mechanical properties measurement by Vickers hardness 5 | P a g e 6. RESULT AND DISCUSSIONS 32-45 [6.1] Chemical analysis of rice husk ash silica [6.2]Bulk density of cordierite glass ceramic [6.3] Phase analysis of cordierite glass ceramic [6.4] Microstructure analysis of cordierite glass-ceramic [6.5] Linear thermal expansion of cordierite glass ceramic [6.6] Vickers hardness for cordierite glass ceramic 7. CONCLUSION 46-47 8 REFERENCES 48-51 6 | P a g e LIST OF FIGURES Figure no Topic Page no 1. High Temperature Dilatometer DIL 402C (NETZSCH) 31 2. XRD pattern of TiO2 nucleated cordierite glass-ceramic heat 35 treated at 850oC for 2 hour soaking period. 3 XRD pattern of TiO2 nucleated cordierite glass ceramic heat 36 treated at three different soaking period a) 850oC (2hr)-1250oC (2hr), b) 850oC (2hr)-1250oC (4hr), c) 850oC (2hr)-1250oC (6hr), . 4. XRD pattern of TiO2 and ZrO2 (mix) nucleated cordierite glass 37 ceramic heat treated at different soaking period. a) 850oC (2hr)- o o o 1250 C (4hr), b) 850 C (2hr)-1250 C (6hr). 5. XRD pattern of and ZrO2 nucleated cordierite glass ceramic 37 heat treated at different soaking period. a) 850oC (2hr)-1350oC o o (4hr), b) 850 C (2hr)-1350 C (6hr). 6. SEM image of TiO2 nucleated cordierite glass-ceramic heat 38 treated for nucleation at 850 OC for (2hr) + 1250 OC with three different soaking period of a) 2hr, b) 4hr and c) 6hr. 7. SEM image of TiO2-ZrO2 (mix) nucleated cordierite glass- 39 ceramic heat treated for nucleation at 850 OC for 2hr +1250 OC with three different soaking period of a) 2hr, b) 4hr and c) 6hr. 8. SEM image of ZrO2 nucleated cordierite glass-ceramic heat 40 treated for nucleation at 850 OC for 2hr+1250 OC with three different soaking period of a) 2hr, b) 4hr and c) 6hr. 9. Linear thermal expansion coefficient of TiO2 nucleated 42 cordierite glass ceramic heat treated for nucleation at 850 OC for 2 hour + 1250 OC with different soaking period as 2, 4 and 6 hour for a) , b) and c) respectively. 7 | P a g e 10 Linear thermal expansion coefficient of cordierite glass ceramic 44 nucleated with three different nucleating agent i) TiO2- ZrO2(mix), ii) TiO2 iii) ZrO2. All samples were heat treated at 850 oC for 2 hour (first stage) and 1250 oC for 4 hour (second o stage) for (TiO2 and TiO2-ZrO2 (mix)) and 1350 C for ZrO2 containing sample. LIST OF TABLES Table no TOPIC Page no 1. Physical property of cordierite 11 2. Advantage and disadvantage of cordierite glass ceramic 12 3. Batch -1 for TiO2 nucleated cordierite glass-ceramic 25 4. Batch-2 for TiO2 and ZrO2 (mix) nucleated cordierite glass- 25 ceramic 5. Batch-3 for ZrO2 nucleated cordierite glass-ceramic 26 6. Bulk density and apparent porosity of cordierite based glass 33 ceramic 7. Phases & position of TiO2 nucleated cordierite glass-ceramic 36 heat treated at 850oC for 2 hour soaking period. 8. The phases & position of TiO2 nucleated cordierite glass-ceramic 41 heat treated at 850oC for 2 hour soaking period. 9. Thermal expansion coefficient and transition zone of temperature 43 of TiO2 nucleated glass ceramic prepared by varying temperature 8 | P a g e and soaking time of heat treatment 10. Thermal expansion coefficient and transition zone of temperature 44 of glass ceramic prepared by three different nucleating agent (Tio2, (TiO2-ZrO2) mix and ZrO2) with varying temperature and soaking time of heat treatment. 11. Vickers’s hardness of glass ceramic prepared by three different 45 nucleating agent (Tio2, (TiO2-ZrO2) mix and ZrO2) with varying temperature and soaking time of heat treatment. 9 | P a g e CHAPTER 1 INTRODUCTION 10 | P a g e INTRODUCTION Cordierite is mainly a ceramic material of magnesium aluminum silicate having formula 2Mgo2Al2O35SiO2. It resembles to hexagonal form of structure (cyclosilicate sheet). It is commonly prepared by oxide powder sintering. Cordierite based glass-ceramics have many attractive properties. This type of material is very good at thermal shock resistance, thermal stability and excellent dielectric property. Cordierite is also called as indialite. Cordierite was discovered in 1813 and is named after the French geologist Louis Cordier (1777-1861). In cordierite three types of basic component are present they are MgO, Al2O3, SiO2. In glass- ceramic technology we can select the composition to optimize the viscosity of the glass and achieve advantageous processing. As cordierite is co-fired with copper at low temperature (below 1000 oC). So it became popular than aluminium nitride. The sintering temperature range of cordierite is close to the melting temperature. Sometimes research groups encounter some difficulties to sinter the cordierite product. By adding sintering aid we can get good mechanical properties along with high dielectric constant and high thermal expansion. Properties Cordierite Chemical formula 2MgO.2Al2O3. 5SiO2 Density 2.60 g/cc Modulus Of Rupture 117 MPa Young’s modulus 70 GPa Thermal expansion coefficient 1.7 (x10-6/°C) Thermal Conductivity 3 W/m K (room temp.) Max. Operating temp. 1371 °C color Gray, white, blue Table 1 - Physical and mechanical properties of cordierite 11 | P a g e In order to develop glaze fully, layer flux are added which matures the glaze layer. So that glaze should have suitable surface tension and thus crawling effect is minimized. To control crystallization some nucleating agents are added. By using nano-sized silicon powder and increasing surface area. Formation of silicon nitride becoming will increase which should be related to Si3N4 formation at low temperature and prevent to reacting with cordierite to form liquid form during sintering. Thermodynamically cordierite exists in two phase’s α-cordierite (high temperature phase, stable) µ-cordierite (low temperature phases) Advantage of cordierite glass ceramic Disadvantage of cordierite glass ceramic High thermal shock resistance Low mechanical property Low dielectric constant & loss Narrow sintering temperature Low thermal expansion Dense cordierite preparation is difficult High thermal stability Monophasic cordierite preparation is difficult High chemical stability Without sintering aid cordierite ceramic preparation is not possible Can be co-fired with copper below1000o c By adding sintering aid its thermal expansion and dielectric constant and dielectric loss increases Table- 2 advantage and disadvantage of cordierite glass ceramic: APPLICATION Catalytic converter are mainly made of from ceramic containing a large proportion of synthetic cordierite.
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