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University Miaorilms International INFORMATION TO USERS This reproduction was made from a copy of a document sent to us for microfilming. While the most advanced technology has been used to photograph and reproduce this document, the quality of the reproduction is heavily dependent upon the quality of the material submitted. The following explanation of techniques is provided to help clarify markings or notations which may appear on this reproduction. 1.The sign or “ target” for pages apparently lacking from the document photographed is “ Missing Page(s)” . I f it was possible to obtain the missing page(s) or section, they are spliced into the film along w ith adjacent pages. This may have necessitated cutting through an image and duplicating adjacent pages to assure complete continuity. 2. When an image on the film is obliterated with a round black mark, it is an indication of either blurred copy because of movement during exposure, duplicate copy, or copyrighted materials that should not have been filmed. For blurred pages, a good image of the page can be found in the adjacent frame. If copyrighted materials were deleted, a target note will appear listing the pages in the adjacent frame. 3. When a map, drawing or chart, etc., is part of the material being photographed, a definite method of “sectioning” the material has been followed. It is customary to begin film ing at the upper left hand comer o f a large sheet and to continue from left to right in equal sections with small overlaps. I f necessary, sectioning is continued again-beginning below the first row and continuing on until complete. 4. For illustrations that cannot be satisfactorily reproduced by xerographic means, photographic prints can be purchased at additional cost and inserted into your xerographic copy. These prints are available upon request from the Dissertations Customer Services Department. 5. Some pages in any document may have indistinct print. In all cases the best available copy has been filmed. University M iaorilm s International 300 N. Zeeb Road Ann Arbor, Ml 48106 8305383 Raynaud, Guy-Michel THE IN-SITU HIGH TEMPERATURE OXIDATION OF OFHC COPPER AND NICKEL The Ohio State University PH.D. 1982 University Microfilms International 300 N. Zeeb Road, Ann Arbor, M I 48106 Copyright 1983 by Raynaud, Guy-Michel All Rights Reserved PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark V . / 1. Glossy photographs or pages ^ 2. Colored illustrations, paper or print_____ 3. 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Other______________________________________________________________ University Microfilms International THE IN-SITU HIGH-TEMPERATURE OXIDATION OF OFHC COPPER AND NICKEL DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Guy-Michel Raynaud ****** The Ohio State University 1982 Reading Committee: Approved By Professor R. A. Rapp Professor J. P. Hirth Professor W. A. T. Clark Department of Metallurgical Engineering ACKNOWLEDGMENTS I would like to thank Professors W.A.T. Clark and J.P. Hirth, Drs. A.N. Khodan and S.K. Verma , Tom Jungling, R. Farrar and J. Ross, for their help during this past period. Three years ago, when I first stepped in Professor R.A. Rapp's office, I noticed a little card perched on his shelf from one of his previous students. It was dedicated to the "world's best adviser." My first impression was one of surprise but now I fully agree and if I were not afraid it would disturb the orderliness of his office, I would gladly give him another one. Financial support of the research by the Department of Energy is grateful ■ acknowledged. VITA June 20, 1957 ......... Born - Montlu^on, Allier, France 1979 ................... B.S. Electrochemistry. Ecole Nationale Superieure d'Electro- chimie et d 'Electrometallurgie de Grenoble, Isere, France 1979-1982 .............. Graduate Research Assistant, The Ohio State University. Columbus, Ohio TABLE OF CONTENTS Page ACKNOWLEDGMENTS ........................................... ii VITA .......................................................... iii LIST OF T A B L E S ........................................... vi LIST OF F I G U R E S .............................................. vii I. INTRODUCTION AND LITERATURE SURVEY ........... 1 A. High Temperature Oxidation of Metals . 1 B. High Temperature Oxidation of Copper . 13 C. High Temperature Oxidation of Nickel . 17 II. EXPERIMENTAL EQUIPMENT, MATERIALS AND PROCEDURES ......................................... 25 A. Literature Survey .......................... 25 B. Modification of the S E M .................. 28 C. Post Oxidation A n a l y s i s .................. 46 III. OXIDATION OF OFHC C O P P E R ........................ 49 A. Introduction .............................. 49 B. Specimen Preparation ..................... 49 C. Results and D i s c u s s i o n .................. 55 IV. OXIDATION OF N I C K E L ...................................159 A. Introduction ................................. 159 B. Experimental Procedure .................. 159 C. Results and D i s c u s s i o n ..................... 163 V. IRREGULAR OXIDE GROWTH, MECHANISMS AND THE EVOLUTION OF SCALE MORPHOLOGY .................... 212 A. Introduction ................................. 212 B. Morphologies and Growth Mechanisms . 213 C. Influence of the T e m p e r a t u r e .............. 228 D. Influence of Water V a p o r ................... 232 iv Page VI.SUMMARY AND CONCLUSIONS............................23 7 A. Oxidation of OFHC Copper in Pure Oxygen . 2 38 B. Oxidation of Ni c k e l ......................... 240 APPENDIXES A .................................................. 243 B .................................................. 247 C. ........................................... 252 D .................................................. 258 E .................................................. 260 LIST OF R E F E R E N C E S ...................................... 262 i v LIST OF TABLES Table Page 1. Equilibrium Partial Pressures for Vapor Species Over Cu and Cu20 at 927°C ........................ 125 2. Number of Successful Collisions for Different Values of C for Modified Copper Flux (Z ) 2 ^ ^ c and for Unmodified Copper Flux (ttR BJ„xh) . 137 nij 3. Chemical Analysis of the 99.999% (Marz grade) Ni Polycrystalline ............................... 160 4. Lattice,Grain Boundaries and Surface Diffusion Coefficients of Ni in NiO^-^, 177,178, 269 230 vi LIST OF FIGURES Figure Page 1. Photograph Showing the Modified Stage .......... 29 2. Photograph Show'ng the Heating Stage and Its Parts ........................................... 30 3. Photograph Showing the Specimen, Heater, Shields, and Cylinder ............................. 31 4. Heating Stage with the Cylinder, Shields, Heater and Specimen in Cross-section ......... 32 5. Calibration of the HSESEM Thermocouple . 38 6. Apparatus for Monitoring and Calibrating Gas Flow into Microscope ............................ 40 7. Calibration of the Flowmeter .................... 42 8. Signal Enhancement Versus Applied Potential on the Top Shield ................................. 45 9. Schematic Diagram of the Hot Stage and EDAX System ......................................... 47 10. Temperature/Pressure Regions of Formation of CU2 O and CuO (x x after Rapp and S h o r e s , 1^5 o o after Honjol^®) .......................... 50 11. Contamination during a 25 hr Run at 950°C from In-situ EDAX Analysis Inside the HSESEM. 53 12. Contamination Detected with an Auger Micro­ scope after Oxidation of Copper at 800°C Inside the HSESEM ................................. 54 13. Oxide Film Formed on Electropolished OFHC Copper at 300°C in P_ = 3x10“^ atm 2 after 20 hours .................................... 59 vi i Figure Page 14. Schematic Growth of CU2 O on OFHC Copper at 300°C and P = 3xl0-4 at m ........................ 59 2 15. Oxidation of Electropolished OFHC Copper at 500°C, P = 3xl0~4 a t m .......................... 60 2 2 16. Plot of -log(l-f) versus t for Three Differ­ ent Grains of OFHC Copper Oxidized at 500°C in Pn = 3xl0“4 a t m .............................. 64 2 17. Oxidation of Electropolished OFHC Copper at 700°C, P = 3x 10“4 a t m .................. 65 Uo 18. Photomicrographs at 1000X showing Cu Specimen Surface when Heated in SEM to 850°C in P = 2x10-5 atm. (1,OOOX)......................U2 . 67 19. Oxidation of OFHC Copper at 820°C for 30 s (2, 00 0 X ) ............................................. 70 20. Morphology of OFHC Copper at 820°C (2,000X) . 72 21. Oxidation of Electropolished OFHC Copper at 500°C in P = 3xl0“4 a t m ....................... 73 2 22. Oxidation of Electropolished OFHC Copper at 500°C in Pn = 3x10“4 a t m ....................... 77 2 23. SEM Photographs of In-situ Oxidation of OFHC Cu Oxidized
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