The aim of this research was the investigation of bonding borosilicate glass sheets, its trade mark CMZ, 100μm thickness, to create multilayer substrates capable of supporting high-density electrical interconnections. CMZ glass was chosen as it has a coefficient of thermal expansion that is close to that of silicon, thereby minimising thermal stresses in assemblies generated by manufacturing processes or service conditions. Two different methods of bonding the glass were used in this study; pressure assisted low temperature bonding (PALTB), and water glass bonding, using Sodium Trisilicate (Na2Si3O7) solution. These two bonding methods have already been applied in electronics manufacturing applications, such as silicon wafer bonding and multichip modules (MCMs). However, glass-to-glass bonding is a relatively new subject and this study is an attempt to standardise bonding processes. Additionally, the concept of using glass as a multilayer substrate provides a foundation for further exploration by other investigators. Initial tests that were carried out before standardising the procedures for these two methods showed that a two-stage bonding process provided optimum results. A preliminary stage commenced by placing the cleaned (using Decon 90 solution) samples in a vacuum oven for 15 minutes, then heating at 100oC for 1hr. The permanent stage was then achieved by heating the samples in a conventional oven at temperatures from 200 to 400oC, for different periods. At this stage, the main difference between the two methods was the application of pressure (1-2MPa) during heating of the PALTB samples. To evaluate the quality of the bonds, qualitative tests such as visual, optical microscope and dye penetrant were used. In addition, to estimate the strength and the rigidity of the interlayer bonds, two quantitative tests, comprising of deflection under cyclic stresses and crack opening were used. Thermal cycling and humidity tests were also used to assess resistance of the bonds to environmental effects. The results showed that heating to 100oC was insufficient to enhance the bonds, as occasionally a sudden increase of deflection was observed indicating slippage/delamination. These bonds were enhanced during the permanent bonding stage by heating to 300oC in PALTB, under a pressure of 1-2MPa. The crack-opening test showed that the delamination distances of the bonds in the permanent stage were lower than that for preliminary bonding in both bonding methods. The delamination distances from the crack opening tests were used to calculate the strain energy release rate (GIC) and fracture toughness (KIC) values of the interlayers. The results showed that the KIC values of the permanent PALTB and water glass interlayers were higher than 1MPa.m0.5, while the KIC value of the CMZ glass, determined by linear elastic fracture mechanics, was around 0.8MPa.m0.5. The optical observations revealed that the prepared bonded sheets did not delaminate or break after thermal cycling and humidity tests.

Since about 1970, there has been growing interest in the use of microwaves for heating and material processing. Microwave heating is fundamentally different from conventional heating in which electrical resistance furnaces are typically used. In microwave heating, heat is generated internally by interaction of the microwaves with the atoms and molecules of the material. Microwave heating has many potential benefits, such as rapid heating, selective heating and low cost [1, 2], these are attributable to the volumetric nature of microwave energy deposition. In addition to the possibility of faster and more controllable temperature ramp-up, microwaves can heat one region or phase more than others due to either the method by which the microwaves are deposited in the material or differences in the dielectric properties. The latter is important during the processing of new ceramic and composite materials. All the above can be treated as the thermal action of the electromagnetic field on matter.

The thesis describes the design and construction of a local area computer network to provide a distributed industrial control and monitoring system for glass container manufacture. In particular, a commercially available local area network, originally manufactured to link industrial programmable controllers, has been used to allow the implementation of multi-processor control scheme for container forming and to achieve an integrated data processing link with other plant computers concerned with inspection and quality data collection. A microprocessor-based I.S. machine controller was designed to replace conventional Timing Drum controllers used in many container manufacturing plants, and linked to the local area network. The control system developed provided the usual machine sequencing functions but also provided adaptive control of the invert mechanism speed using a specially designed electropneumatic servo mechanism valve. A data capture system was also designed, developed and tested to allow' on-line monitoring of container inspection machines. The system utilises the local area network to provide access to a file server (for data storage), to allow remote access (e.g. in Quality Control) and to establish a link with the I.S. machine controllers. The distributed control and monitoring scheme produced allows the convenient integration of other data processing functions in other plant areas such as batch, furnace, forehearth, and packing and can facilitate the integration of organisational functions such as planning, scheduling, and data base management in a planned step by step manner.

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No description available.

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PA3200 is a material developed by EOS GmbH and is a mixture of PA2200 polyamide powder and glass beads. PA3200 is used to produce sintered parts via a rapid prototyping process known as Selective Laser Sintering (SLS) or simply Laser Sintering (LS). This thesis reports on an experimental investigation based upon a commercially available LS machine (a Sinterstation 2500 HiQ from 3D Systems Inc) into how heat and the glass content affect the material. The main aim of the research was to determine the ranges of process parameters and ratios of glass/polyamide and used/virgin materials needed to produce good quality parts, i.e. parts that are dense and geometrically accurate and do not display a rough orange-peel-like surface. The thesis presents the design of experiments, the experimental procedure adopted and the results of the tests conducted. The latter included assessments of the thermal and flow properties of the material via Differential Scanning Calorimetry (DSC) and Melt Flow Rate (MFR) measurements, a study of the crystallisation behaviour of powder using gel permeation chromatography (GPC) to evaluate changes in molecular weights and visual examination of the microstructure of the sintered parts via optical microscopy. The experimental work involved controlling parameters such as the laser power, laser speed, scan spacing, layer thickness and part bed temperature. The results obtained confirm that the melt viscosity of the material increases with the glass content and decreases with temperature. Also, as expected, exposing the material to elevated temperatures causes it to deteriorate and increasing the proportion of recycled material (that has been exposed to high temperatures) adds to the risk of producing parts with an orange-peel like surface. The thesis derives empirically-based recommendations for the minimum MFR value, the maximum glass/polyamide mass ratio and the maximum recycled/virgin materials ratio to ensure the production of parts not affected by the orange peel problem.

An outline of the use of titanium in glass ceramic production is given. To investigate the role of titanium in this process a variety of procedures were necessary. These included X-ray diffraction, Electron microscopy, Optical measurements and Electron spin resonance. Two main approaches to the investigation have been adopted, the first is through the observation of the effects of crystallisation on gadolinium introduced into the glass matrix. The interpretation of the electron spin resonance for gadolinium in terms of a spin hamiltonian has led to the suggestion of two sites for this rare-earth ion. A crystal growth inhibition has been found to be produced by the incorporation of gadolinium in the lithia alumina silica glass ceramics. The alternative method of investigation is concerned with X-ray?. induced defects and the results have been interpreted in terms of local well ordered domains existing within the glass.

The objective of this work was twofold, i.e. to develop an aqueous route for tape casting Lead Ziconate Titanate (PZT)ceramics for pyroelectric applications and to optimise the die-pressing route for reducing defect size and number in bulk Lead Zicronate Titanate ceramics (PZT).