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Results of a study of the production of hollow-ware by deep-drawing and bulge forming are presented. Axisyrnrnetrical and asymmetrical shapes were successfully produced from soft aluminium flat blanks in one stroke of a punch. The process consists of drawing, ironing and bulging inside a closed die cavity. The constituent operations are studied individually. In deep drawing without a blank-holder, an approach to convex type die design is presented. The investigation evaluates the effect of die profile geometry on the drawing performance. Three dies of the second degree spiral type,one near to the tractrix shape and the other two with larger radius of curvature, are considered. The materials tested include mild steel, stainless steel, soft aluminium and brass. The drawing process through tractrix, exponential spiral, second degree spiral and conical type dies is analysed using a numerical solution formulated earlier and the theoretical results on the punch load and the strain development are compared with the experimental results. Good correlation is obtained on the development of strains. The theoretical prediction of the punch load is reasonably good except for mild steel which is highly anisotropic. It is shown that by modifying the die profile, the 'punch load can be significantly reduced. The reductions predicted by theory are in good agreement with experiment which means that optimum die design for minimum load is possible. In ironing of cups, using soft aluminium blanks, it was found that punch speeds in the range 7-45 rom/sec have negligible effect on the drawing load. The ironing load decreases slightly as the speed increases in this range. The reduction is more significant with higher degrees of ironing. Measurement of ironed cup wall thickness showed that thickness variations are attributed to planar anisotropy of the blank and geometrical errors in tooling. Free bulge forming is used as a simplified approach to closed die forming. The bulge profile modes under different loading conditions of internal pressure and axial force, the effect of the unsupported cup length and the effect of the cup wall thickness on the bulge ratio were investigated using a specially designed test rig. For bulging of as deep-drawn cups, the bulge ratio increases with increase of cup wall thickness, and it decreases with increase of length. For bulging of annealed cups the length effect is negligible and the bulge ratio increases slightly with increase of cup wall thickness. The procedure used in producing different hollow-ware. shapes is described together with typical failure examples. The thickness reduction and bulge ratio distributions are shown and comparison is made between annealed and as deep-drawn cups.

This research investigates metallurgy during the sixteenth and seventeenth centuries in Colombia. Drawing on theories from Material Culture Studies, Landscape Archaeology and the Anthropology of the Senses, and adopting a multidisciplinary approach that includes archaeological evidence, documentary sources and ethnographic interviews, this study aims at documenting and analysing what happened to metallurgy after the encounter. The study focuses on the town of Mompox, a World Heritage Site, in the Momposino Depression in northern Colombia. Here, a long-lasting metalwork tradition survives not only in the memories of the oldest goldsmiths but also in delicate silver filigree work. The study focuses on the relationships that emerged between things and people within different landscapes and in light of this it offers an alternative perspective to examine processes of change and transformation, movement, continuity, resistance, techniques, and experiences. This thesis argues that the entangled relationship among individuals, objects and landscapes brought important tensions and sensorial experiences into play, which in turn altered, resignified, modelled and influenced the metallurgical activity. This research is the first attempt at studying metalwork during the early colonial period in Colombia from a multidisciplinary perspective. It discusses the material record left by metalwork in the past that was recovered during excavations in Mompox. Archaeometallurgical analysis' results contribute to the discussion. From a historical point of view, primary sources, chronicles of Indies and official reports shed light on goldsmithing activity, the characteristics of workshops, and the social, economic and political circumstances of metalwork activity within this time frame. Finally, from an anthropological perspective, interviews with older goldsmiths in Mompox provide an ethnographic dimension to help understand present-day metalwork and to search for traces of the material culture remains.

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In recent years, the rapid progress in the field of maohine tools has necessitated a more accurate determination of the cutting forces for design purposes than has been possible in the past. In the milling operation, the chip section changes along the cut and this change causes a fluctuation of the cutting force. The designer of milling machines must know the maximum force values and the amplitudes of the force pulsations, whilst the user must be able to select cutting conditions which will keep the pulsations within permissible limits. The investigation was started by improving a Three-Component Milling Dynamometer, details of which have already been published. The modifications aimed at a high natural frequency and greater measuring sensitivity. They were: (1) Increased stiffness of the measuring rings (2) Reduced weight of the top plate (3) Modifications of the electrical circuit The dynamoneter was capable of measuring from 1.5 to 1500 lb. and had a natural frequency of 720 cycles per sec. in its weakest direction and could thus be used up to 180 cycles per second, without the dynamic magnifier exceeding about 5%. The investigation into the chip section and cutting forces covered both slab and face milling.

Welding of austenitic stainless steels is a prominent process in several industrial sectors including nuclear, aerospace, chemical and process. During finite element modelling of weld properties, it is assumed that the weld metal is homogeneous. During the modelling process weld metal is assigned the same elastic constants as that of parent metal. This can introduce erroneous results during the calculation of strains. Weld metal is usually highly anisotropic due to directional solidification. Weld metal also possessesty pical fibre texture as the grains grow along the maximum thermal gradient when cooling and the result is long, columnar grains. These grains usually have a particular crystallographic direction along the solidification direction. Weld metals usually have [0011 crystallographic planes along the solidification direction, and it has been termed as [0011 fibre texture. The resulting fibre texture due to solidification has an important consequence on weld metal properties. Depending on the grain orientations, different mechanical properties are observed as compared with an ideal homogeneous and isotropic material. Different types of austenitic weld metals have been investigated in this work. The mechanical response of different types of weld metal, in different directions has been analysed using in-situ tension/compression and neutron diffraction. It has been observed that the Young's modulus for the weld metal is direction dependent. These variations have been explained on the basis of texture investigation using the electron backscatter diffraction (EBSD) technique. The texture results have been correlated with the material response and it has been observed that the more pronounced the crystallographic texture, the more anisotropic is the material response under applied loading. Finally, the directional Young's modulus has also been calculated from elasto-plastic self-consistent modelling using Hutchinson's formalism (using the FORTRAN sub-routine written by Carlos Tome).

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