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The purpose of this paper is to perform an analytical study of non-linear elastic delamination fracture in the multilayered functionally graded split cantilever beam (SCB) configuration. The SCB studied may have an arbitrary number of vertical layers. The material in each layer is functionally graded along the layer thickness. Also, the material properties may be different in each layer. The analytical solution derived was applied for parametric investigations in order to evaluate the effects of material properties and delamination crack location on the non-linear fracture behaviour.

The delamination fracture was studied in terms of the strain energy release rate. The SCB mechanical response was described by using a power-law stress-strain relation. A non-linear analytical solution for the strain energy release rate was derived by considering the SCB complementary strain energy. In order to verify the solution, an additional analysis of the strain energy release rate was developed by considering the complementary strain energy in the beam cross-sections ahead and behind the crack front.

The effects of material gradient, crack location along the beam width and non-linear material behaviour on the delamination fracture were evaluated. The analytical solution derived is useful for parametric studies of non-linear fracture in multilayered functionally graded beams.

Delamination fracture in the multilayered functionally graded SCB configuration was analysed with considering the non-linear material behaviour.

The purpose of this paper is to deal with an analytical investigation of delamination fracture in the mixed-mode bending (MMB) multilayer beam configurations taking into account the material non-linearity.

The J-integral approach was applied in fracture analysis. The beam layers non-linear mechanical response was described by using a power-law stress-strain relation with four material constants. Analytical solutions of the J-integral were derived by using the technical beam theory. The fracture analysis developed is valid for MMB beams whose layers may have different thicknesses. Also, the values of material constants in the non-linear stress-strain equation may be different for each layer.

The effect of material constants, crack location and layer thicknesses on the non-linear fracture was evaluated. The analytical solutions obtained are very suitable for parametric studies of non-linear fracture behaviour. The approach developed here can be used for optimization of multilayered beam structures with respect to the delamination fracture performance. The present study can also be useful for the understanding of fracture in multilayered beams exhibiting material non-linearity.

For the first time, an analytical study was performed of the delamination fracture behaviour of the MMB multilayered beam configuration taking into account the material non-linearity.

This study aims to characterize a novel glass/epoxy architecture sandwich structure for electronic boards. Understanding the thermo-mechanical behavior of these composites is important because it is possible to pre-determine whether defined “internal” thick laminates will be suitable for embedding components in the direction of the axis “z,” i.e. this method of manufacturing multilayer laminates can be used for incoming miniaturization in electronics.

Laminates with a low glass transition temperature (Tg) and high Tg with E-glass type were treated, tested and compared. Testing samples were manufactured by nonstandard two steps unidirectional lamination as a multilayer structure based on prepreg layers and as “a sandwich structure” to explore its effect on thermo-mechanical properties. The proposed tested method determines the time and temperature-dependent viscoelastic properties of the board by using dynamic mechanical analysis, thermo-mechanical analysis and three-point bend tests.

This testing method was chosen because the main property that promotes sandwich structure is their high stiffness. Glass/epoxy stiff and thermal stabile sandwich structure prepared by nonstandard two-stage lamination is proper for embedding components and the next miniaturization in electronics.

Compared with by-default applied glass-reinforced homogenous laminates, novel architecture sandwich structure is attractive because of a combination of strength, stiffness and all while maintaining the miniaturization requirement and multifunctional application in electronics.

The purpose of this paper is to present an analytical study of the delamination fracture behaviour of a multilayered two-dimensional functionally graded cantilever beam configuration. A delamination crack is located arbitrary along the height of the beam cross-section. The layers have different thicknesses and material properties. Perfect adhesion is assumed between layers. The material is functionally graded in both thickness and width directions in each layer. Besides, the material of the beam exhibits non-linear-elastic behaviour.

The delamination fracture behaviour is analysed in terms of the strain energy release rate. The J-integral approach is applied in order to verify the analysis of the strain energy release rate developed in the present paper.

The influence of material properties, the crack location along the height of the beam cross-section and the non-linear behaviour of the material on the delamination fracture is examined.

A non-linear delamination fracture analysis of multilayered two-dimensional non-symmetric functionally graded beam configuration is developed.

Diffusion patterning is a dielectric patterning technology, which is used in the screen printed thick film technology for higher density multilayer circuits. This technology is suitable for producing lower cost multichip modules and requires a low additional investment in conventional thick film technology production lines. Comparisons of via resolution capability of diffusion patterning versus conventional thick film technology are described and discussed. Preliminary experimental results obtained with a test circuit showed that 200μm lines and 200μm vias could be achieved with acceptable yield and with minimal modification to standard production lines. The electronic circuit for the pressure sensor was designed and realised with the verified technology as a low‐cost ceramic multichip module. A few results of an investigation of some thick film materials, which comprise the “set” of pastes for diffusion patterning technology, are presented.

High demands are placed on base materials for present‐day printed circuits. The requirements for multilayer materials are examined including satisfying criteria regarding low dielectric constant, high glass transition temperature and dimensional stability. Comparisons are made involving different resin systems and reinforcement materials. Improvements in material characteristics are often accompanied by disadvantages in terms of processability, copper peel strength and price. The properties of a number of paper‐based laminates and their requirements are discussed. It is concluded that no ‘ideal’ base material is available which simultaneously fulfills all demands including price.

Those Circuit World readers aware of the writer's appreciation of the varied delights of regional cuisine may be forgiven for assuming that the above choice of venues was determined by some personal predilection for Lancashire Hotpot and Mignon de porc à la graine de moutarde (of the Dijon variety, of course). There was, admittedly, a brief opportunity to savour the local fare in each case, but the real purpose of these successive visits was to ‘explore’ the activities at New England Laminates Company's two European production facilities.

Printed Circuit World Convention 5, which took place at the Forum Hotel and Scottish Exhibition & Conference Centre, Glasgow, from 12–15 June 1990, will be reported in two parts. Part 1, in this issue, covers an introduction to the event, the Opening Ceremony and a number of the technical sessions. The remaining technical sessions will be reported in Part 2 in the following issue.

The purpose of this paper is to examine the issues affecting end of life (EOL) management of flexible packaging. It focuses on Sustainable Solid Waste Management by using multi-criteria decision making, analytic network process (ANP), and Strengths, Weaknesses, Opportunities, and Threats (SWOT).

Data were collected from 33 expert stakeholders, though a series of interviews and questionnaires. The subject seven aspects were applied from integrated sustainable waste management with 19 sub-criteria identified. Criteria were prioritized by using ANP and SWOT to the internal and external environments of organizations directly responsible for waste management.

The five most important factors in the management of flexible packaging waste include: techniques for waste management, material and design, management support, legislation and rule, and environmental care and environmental health, respectively. Solutions addressing flexible packaging waste were identified, including reuse and recycle, waste to energy, biopolymers, new innovative materials and material recovery.

Data were derived from the national authorities and large companies. The findings may not represent local authorities and small-scale manufacturers. Future research should be conducted, in order to investigate and focus around small manufacturing enterprises.

The findings provide a strategic framework for policy makers and industrial manufacturers. The benefits of this will enable them to address flexible packaging waste, by using qualitative and quantitative criteria.

This is the first paper developing a multi-criteria assessment model to specifically manage EOL flexible packaging, a possible pioneering piece of research in this field.

This paper aims to give a survey of incoming inspection of raw materials—an integral part of Quality Assurance in the printed circuit industry—describing some test methods and parameters for testing primary materials.