Technical Report 2 National Science Foundation Grant DMR 09-04096 Metals Program Indium solubility in α-gallium and gallium-indium eutectic alloys studied using PAC by Xiangyu Yin August 2011 Hyperfine Interactions Group Department of Physics and Astronomy Washington State University Pullman, Washington 99164 USA Foreword This report is the MS thesis of Xiangyu Yin, defended May 9, 2011. The research described herein was supported in part by the National Science Foundation under grant DMR 09-04096 (Metals Program). Gary S. Collins mailto:[email protected] May 2011 INDIUM SOLUBILITY IN α-GALLIUM AND GALLIUM-INDIUM EUTECTIC ALLOYS STUDIED USING PAC by XIANGYU YIN A thesis submitted in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE IN PHYSICS WASHINGTON STATE UNIVERSITY Department of Physics and Astronomy AUGUST 2011 ACKNOWLEDGEMENT I would like to thank my advisor Professor Gary S. Collins for his patient guidance and assistant with my research. I would also like to thank Randy Newhouse, John Bevington for their help and advice on my experiments. Discussion with Dr. Heinz Haas was also appreciated. I would like to express my gratitude to my parents for their encouragement and support. iii INDIUM SOLUBILITY IN α-GALLIUM AND GALLIUM-INDIUM EUTECTIC ALLOYS STUDIED USING PAC Abstract by Xiangyu Yin M.S. Washington State University August 2011 Chair: Gary S. Collins The melting temperature of α-gallium is 303K. The method of perturbed angular correlation of gamma rays (PAC) was used to determine the solubility of 111In probe atoms present at of 10-10 mole fraction. Below 303K and above the eutectic temperature of the gallium-indium binary system, approximately 10% of probes were observed through measurements of nuclear quadrupole interactions to be dissolved in solid gallium. This makes the terminal solubility about 10-11. Below the eutectic temperature, where the only stable phases are gallium and indium metals, the remaining 90% of indium probes, previous being in the liquid phase, were observed to crystallize into tetragonal indium metal, forming crystals of radioactive 111In. In other experiments, about 1% of natural indium or other elements were added to the sample to see their effects on the eutectic reaction. It turns out that bismuth, cadmium and zinc precipitate independently of indium, while tin precipitates with indium. Cadmium-indium alloy at indium-rich region was also studied. Transformation between αT and αK phases are observed. The effect of cadmium impurities on indium metal signal is observed to be small. Mercury-indium system at mercury-rich region was also studied as another example of studying the boundary of binary phase diagram using PAC technique. The terminal solubility of indium in solid mercury was found to be greater than the 10-8 mole fraction of 111In in the samples. iv TABLE OF CONTENTS ACKNOWLEDGEMENT ................................................................................................. iii ABSTRACT ....................................................................................................................... iv LIST OF TABLES ............................................................................................................ vii LIST OF FIGURES ......................................................................................................... viii Chapter 1: Introduction ....................................................................................................... 1 Chapter 2: Experimental Methods ...................................................................................... 2 2.1 PAC ....................................................................................................................... 2 2.1.1 Introduction to PAC ..................................................................................... 2 2.2 Closed-cycle Helium Refrigerator .................................................................. 5 2.2.1 Installation.................................................................................................... 5 2.2.2 Operation and Temperature Accuracy .......................................................... 6 2.3 Sample Preparation ............................................................................................... 7 2.3.1 Gallium with 111In ........................................................................................ 7 2.3.2 Gallium with 111In and ~1 at.% of other elements ....................................... 8 2.3.3 In-Cd Alloys ................................................................................................. 8 Chapter 3: Theory ............................................................................................................... 9 3.1 Crystal Structures of Ga, In and others ................................................................. 9 3.1.1 Gallium ........................................................................................................ 9 3.1.3 Mercury, Tin and Cadmium ........................................................................11 v 3.2 Binary phase diagram of Ga-In system and the calculation of the solubility ..... 12 3.2.1 Binary phase diagram of Ga-In system ...................................................... 12 3.2.2 Method for determination of the terminal solubility .................................. 13 3.3 Eutectic alloy and eutectic reaction .................................................................... 15 3.4 Crystal structures of indium alloyed with several percent of cadmium.............. 17 Chapter 4: Experiments..................................................................................................... 20 4.1 Solubility of In in solid α-Ga .............................................................................. 20 4.1.1 The measurement of solubility ................................................................... 20 4.1.2 A test to determine the amount of natural indium ...................................... 22 4.1.3 The effect by adding 0.7 at.% of natural In ............................................... 27 4.2 Coarsening of morphology of eutectic alloy ....................................................... 27 4.2.1 System having only 111In ............................................................................ 27 4.2.2 System having natural In ........................................................................... 31 4.3 EFG in In-Cd alloys ............................................................................................ 32 4.4 The effect on forming eutectic alloy by adding other natural impurities ............ 37 4.5 Hg-rich region of the Hg-In binary system ......................................................... 41 Chapter 5: Summary ......................................................................................................... 45 APPENDICES………………………………………………………………………….. 46 A. Two mysteries in the literature solved . .............................................................. 46 B. Temperature dependence of quadrupole interaction frequency of α-Ga ............. 48 BIBLIOGRAPHY………………………………………………………………………51 vi LIST OF TABLES Table 1. Temperature to melt the samples……………………………………………..8 Table 2. The identification of phases from PAC spectra………………………………12 Table 3. The change of c/a ratio in In-Cd alloy with respect to composition at 25℃…18 Table 4. Signal observed in Ga-X-In ternary system…………………………………..40 Table 5. Temperature dependence of quadrupole interaction frequency and symmetric parameter of α-Ga…………………………………………………………….48 vii LIST OF FIGURES Fig. 1. Decay of 111In to 111Cd……………………………………………………………2 Fig. 2. PAC electronics schematic………………………………………………………..4 Fig. 3. The Configuration of Close Cycle Helium Refrigerator System…………………6 Fig. 4. Pressure-temperature phase diagram of Ga……………………………………….9 Fig. 5. Crystal Structure of α-Ga………………………………………………………..10 Fig. 6. Crystal Structure of In…………………………………………………………... 11 Fig. 7. Ga-In binary phase diagram……………………………………………………..13 Fig. 8. When the mole fraction of In less than the solubility limit……………………...14 Fig. 9. When the mole fraction of In greater than the solubility limit…………………..14 Fig. 10. Binary phase diagram for completely soluble system in both solid and liquid State……………………………………………………………………………..16 Fig. 11. Binary phase diagram for system having limited solubility in solid state………16 Fig. 12. Cd-In binary phase diagram…………………………………………………….17 Fig. 13. The change of c/a ratio in In-Cd alloy with respect to composition at 25℃……18 Fig. 14. Spectra for 8N Ga w/ 111In at 290K……………………………………………..20 Fig. 15. The definition of B parameter…………………………………………………..21 Fig. 16. Scheme of run sequence on logarithm scale of Ga-In phase diagram………..…23 Fig. 17. Spectra for 8N Ga w/ 111In at 290K after one half-life………………………….24 Fig. 18. Spectra for 8N Ga w/ 111In at 290K after two half-lifes………………………...25 Fig. 19. Evolution of 푓푎푙푝ℎ푎;퐺푎 with background parameter…………………………..26 viii Fig. 20. Spectra for Ga w/ 0.7 at.% natural In at 290K…………………………...27 Fig. 21. Change of the spectra of 111In crystal with temperature………………………29 Fig. 22. Temperature dependence of the percentage of the offset signal for 111In Crystal………………………………………………………………………...29 Fig. 23. Lattice parameter and their ratio for indium microclusters as a function of average cluster diameter and number of atoms per cluster……………………30 Fig. 24. Comparison of Ga with only 111In and Ga with 0.7 at.% natural In…………...31 Fig. 25. Spectra