عزير بن عاصم © © UZAIR BIN ASIM 2015 ١٤٣٧ هـ iii Dedication Dedicated to my beloved Parents and my Family, who have always been my nearest ones, so close to me that I found them with me whenever I needed. It is their presence in my heart and mind which motivates me to complete my Masters far from my home country. It is their unconditional love and support that motivates me to set higher goals in life and then work untiringly to achieve them. They supported me whenever I needed even in the worst scenarios with their strong and gentle soul which taught me to trust in ALLAH ( ) and to believe in hard work and myself. iv ACKNOWLEDGMENTS First and foremost, I like to express my reverence and prostrate myself to ALLAH ( ) for blessing me such knowledge, health and strength that I am able to be awarded this MS degree and plenteous Salawat to our most beloved Holy Prophet Muhammed ( ). Then, I would like to convey my heartfelt gratitude to my beloved Parents ( ) whose prayers, support and motivation were the only fuel to bring my car of efforts to the destination of MS degree. I would like to express my sincere indebtedness to Prof. Dr. Anwar Khalil Sheikh for being an extraordinary thesis supervisor for my MSc, who showed me the road and helped to get me started on the path to the degree. His enthusiasm, encouragement, and faith in me throughout have been extremely helpful. He was always available for my questions and he was positive and generously of his time and vast knowledge. He always knew where to look for the answers to obstacles while leading me to the right source, theory, and perspective. Also I would like to thanks other committee members, Dr. Sulaiman Pashah, Dr. Sohail Akhtar, whose support, patience and cooperation towards my thesis are really admirable. In addition special thanks and appreciation are given to Mr. Hassan Iqbal, who introduced me to the MAGMASOFT simulation software and providing me necessary assistance and support in shorter span of time before leaving. And to all lab technicians especially Mr. Abdur Rahim (metal casting), Mr. Lateef Hashmi (Material Characterization) and Mr. Agua Romeo (Machining) for providing their expertise in respective fields, facilitated me for the validation of the simulated results. Lastly, I would like to thanks King Fahd University of Petroleum and Minerals and Mechanical Engineering department for providing me necessary equipment, materials and opportunities for carrying and completing my research work with ease. v TABLE OF CONTENTS ACKNOWLEDGMENTS ............................................................................................................. V TABLE OF CONTENTS ............................................................................................................. VI LIST OF TABLES ........................................................................................................................ IX LIST OF FIGURES ....................................................................................................................... X ABSTRACT ............................................................................................................................... XIV ARABIC ABSTRACT .............................................................................................................. XIV CHAPTER 1 INTRODUCTION ................................................................................................. 1 1.1 Metal Casting ........................................................................................................................ 2 1.2 Defects in Castings ............................................................................................................... 3 1.3 Types of Casting Processes .................................................................................................. 5 1.4 TEKALOY VS. ZAMAK Alloy .................................................................................................. 6 1.4.1 Specifications ........................................................................................................................ 6 1.4.2 Physical and Mechanical Properties ................................................................................... 8 1.4.3 Industrial Applications ........................................................................................................ 9 CHAPTER 2 LITERATURE REVIEW ................................................................................... 10 2.1 Research Background ......................................................................................................... 11 2.2 Research Motivation ........................................................................................................... 18 2.3 Research Objectives ............................................................................................................ 19 CHAPTER 3 EXPERIMENTAL METHODOLOGY .............................................................. 22 3.1 Selection of Test Part and CAD Modeling .......................................................................... 24 3.2 Mold Designing by Best Industrial Practices .................................................................... 24 vi 3.3 Process Sequence of Molding Techniques ......................................................................... 44 3.3.1 Sand Mold Casting ............................................................................................................... 44 3.3.2 Plaster Mold Casting ........................................................................................................... 46 3.3.3 Ceramic Mold Casting using 3D Print Pattern-less Z-Cast Technique ............................. 49 CHAPTER 4 OPTIMIZATION OF THE MOLD DESIGN USING NUMERICAL SIMULATION TOOL ................................................................................................................ 51 4.1 Introduction to the Numerical Simulation Tool ............................................................... 52 4.2 Simulation Sequence in MAGMASOFT® ............................................................................. 54 4.2.1 Geometry Modeling (Preprocessing) ................................................................................ 56 4.2.2 Material Definition, Boundary Conditions and Feeding Characteristics ........................ 58 4.2.3 Mesh Generation for VOF Finite Elemental Analysis ........................................................ 59 4.3 Mold Design Optimization by Iterative Simulations ........................................................ 60 4.3.1 Filling and Solidification Behavior .................................................................................... 63 4.3.2 Flow Rate, Pressure and Thermal Behavior ..................................................................... 64 4.3.3 Stress-Strain Behavior at Solidification ............................................................................ 69 CHAPTER 5 VALIDATION OF SIMULATED MOLD DESIGN BY REAL TIME CASTING ..................................................................................................................................... 71 5.1 Mold Making for the Validation of Simulated Results and Comparative Assessment of Products of Gravity Casting Methods ................................................................................. 71 5.1.1 Plaster Mold Casting ........................................................................................................................... 72 5.1.2 Sand Mold Casting ............................................................................................................................... 74 5.1.3 Pattern-less 3D Printed Mold Direct Metal Casting .......................................................... 76 5.2 Validation of Simulated Results by Material Characterization ....................................... 78 CHAPTER 6 SPIN CASTING OF ZINC ALLOY .................................................................... 79 6.1 Spin Casting (Semi-Centrifugal Casting) ............................................................................ 79 vii 6.2 Experimental Setup ............................................................................................................................ 80 6.3 Semi-Centrifugal Spin Casting Experimental Studies ....................................................... 85 CHAPTER 7 PARAMETRIC ANALYSIS OF SPIN CASTING: STUDYING PROCESS CAPABILTIES AND LIMITATIONS ...................................................................................... 87 7.1 Process Capabilities and Limitations ................................................................................ 87 7.2 Parametric Analysis of Spin Casting Process .................................................................... 88 7.3 Predictive Models Development for Porosity and Tensile Strength ............................... 97 7.3.1 Predictive Model for Porosity ............................................................................................ 98 7.3.2 Predictive Model for Tensile Strength ............................................................................. 106 CHAPTER 8 QUALITY ASSESSMENT OF CAST PRODUCTS ...................................... 119 8.1 Material Characterization ................................................................................................ 119 8.2 Scanning Electron Microscopy and Optical Microscopy ................................................. 120