The report describes continuing research on interfacial wear reactions in mechanical face seals. The wear of commercially pure nickel and nickel-20 atomic percent molybdenum was investigated. Tests were run under conditions simulating the wear of mechanical face seals, relative velocity of sliding was 975 centimeters per second. Scanning electron microscopy was used to observe and characterize surface topography. Thin film transmission electron microscopic observations of regions of the alloy cut parallel to the surface of the wear track were made.
Masters Theses in the Pure and Applied Sciences was first conceived, published, and dis seminated by the Center for Information and Numerical Data Analysis and Synthesis, (CINDAS) *at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the ac tivity was transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all concerned if the printing and distribution of the volume were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 19 (thesis year 1974) a total of 10,045 theses titles from 20 Canadian and 209 United States universities. We are sure that this broader base for theses titles reported will greatly enhance the value of this important annual reference work. The organization of Volume 19 is identical to that of past years. It consists of theses titles arranged by discipline and by university within each discipline.
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The study of mechanical seal interfacial wear was made using dry nitrogen gas as the sealed fluid and both industrially pure nickel and some nickel-chromium alloys were used as seal ring materials. The experimentally produced wear reactions were studied metallurgically using optical and electron microscopy. For optical investigations, each seal ring was cut at an angle of five degrees to the worn surface in order to elongate the wear impressions. Surface replicas and chemically thinned sections were produced for electron microscopic studies. The data gathered for detailed investigation were photomicrographs of selected wear areas. Stereographic pairs of most wear areas were taken to aid in documenting the surface irregularities observed, by producing a three dimensional effect to the viewer. Photomicrographs of the thin films were taken to make possible the study of the sub-structure of the material immediately below the wear track. (Author).
