Precision surface finishes are used in a wide variety of applications. From bearing races and rolling elements to parallel slide ways, the frictional characteristics of these surfaces are critical to the performance of the products. Experimental trial and error has shown that certain surfaces outperform others in certain applications, but the specific surface characteristics that make this true have yet to be fully understood. The research goal was to develop an apparatus that can test the coefficient of rolling/sliding friction of different precision machined surfaces and to combine this data with topographic analysis of the surfaces to correlate specific 3-D parameters with the frictional performance of a surface. The sample treatments consisted of four different surface textures (hard-turned, ground, honed and isotropic finish) and four different relative surface speeds. By monitoring the torque in the sample-mounting shaft under lubricated conditions the coefficient of rolling/sliding friction of each surface was found. Utilizing white light interferometry measurement of the surfaces, a highly detailed map of each surface was obtained. Using different characteristic values of each machined surface (RMS roughness, asperity density, lay direction, etc.), the frictional behavior of the surfaces were compared to the surface characteristics yielding insight into the relationship between surface finish and friction in rolling/sliding contact. Friction coefficient was found to correlate most strongly with RMS roughness (Sq) and density of surface summits (Sds). These parameters govern mechanical interference of asperities and surface adhesion respectively. These findings suggest that friction coefficients of surfaces could be optimized through manipulation of three-dimensional surface parameters.

This thesis investigated the microstructure and mechanical property of RRR( high purity) and RG (low purity) niobium (Nb) sheet material. RRR Nb is used in the fabrication RF cavities. Our method involves processing bulk niobium by equal channel angular extrusion (ECAE) and then cross rolling to obtain sheets. This work is a study of the effect different thermomechanical processing variables have on the microstructure niobium sheets. Recrystallization behaviors strongly depended on the purity levels. Tensile tests on sheets clearly indicated the anisotropy in the sheet material. The ductility of the sheet was found to be the largest at an angle of 45o to the rolling direction. There was no apparent relationship observed in the yielding behavior in the different samples. The formability of the sheet measured by the anisotropy ratio suggested a strong dependence of anisotropy on texture. Texture results obtained show that different routes of ECAE can lead to variety of textures in final sheet material. Correlations between the microstructure and the ECAE routes suggest that effective control of microstructure is possible by the thermomechanical steps followed in this study.

Thesis--M. Phil., University of Hong Kong, 1987.

Thesis (M.S.)--Ohio University, November, 1996. / Title from PDF t.p.

Thesis (M.S.)--Ohio University, March, 1994. / Title from PDF t.p.

Thesis (M.S.)--Rochester Institute of Technology, 1990. / Includes bibliographical references.

Thesis (M.Eng.)(Mechanical)--University of Pretoria, 2004. / Includes summary. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 282-288).

The determination of the pressure distribution generated along the arc of contact between the rolls and workpiece during the rolling process has been a subject of interest to researchers for many years. Existing rolling theories make assumptions and include simplifications which are not often substantiated by direct measurement techniques in which pressure transducers are located within the roll surfaces. Such techniques are effective but prohibitively expensive since they render the rolls useless for rolling. A technique has been developed in which the pressure distribution and roll separating load are determined from consideration of the elastic deformation of the rolls during operation. By interrupting a rolling pass before completion, the shapes of the deformed rolls are imparted to the workpiece surface. Accurate measurement of the imparted profiles at several sections across the width of the workpiece allows the extent of the elastic deformation of the roll to be determined. An analytical solution based on solid body contact theory was used to determine the pressure distribution responsible for the elastic deformation along each section. The solution incorporates experimentally determined parameters and functions relating to specific mill-stands and schedules. Initial experimental work was undertaken in which the proposed technique was applied to the quasi-static indentation of flat and inclinedstrip specimens. Having established the basic features of the method relating to these modes of deformation the technique was then applied to the cold rolling process in the form of interrupted rolling passes. Tests were undertaken using a two-high laboratory rolling mill reducing the thickness of mild steel strip workpieces. Comparisons between the predicted pressure profiles using the technique developed and those determined by others using pressure transducers show close similarities. A comparison between the predicted roll separating loads and those determined experimentally show a reasonable correlation.

Budget and budgeting have become more than just control mechanisms over the past few years. They are seen as functions for strategic planning and a method to implement or assist the strategy implementation. The research report investigated whether the budget is a strategic enabler though different contributors of the budgeting process.In previous research the dissatisfactions of the budgetary process were identified, but this excluded the impact that the budget process had on the strategic plans of an organisation. Other research was done on how strategy was done in organisations, but not which methods or instruments were used to implement strategy in organisations. This study investigated the experiences and the views of financial and non-financial senior managers and executives on the budgetary process factors that would influence the implementation of the strategic plan of the organisation. In order to understand the views of the participants, a qualitative research approach was taken in the form of semi-structured expert interviews.The findings reflect that some of these factors that were identified do contribute to the budgeting process and to the budget for being a strategic enabler in an organisation. The surprising findings were that the non-financial respondents did not believe that the use of balanced scorecards would attribute to the implementation of a strategy and that the respondents did not agree to the cycle time of the budgets proposed. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted