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This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

The main purpose of the paper is to propose a new approach to stochastic computational modeling of interface defects in fiber‐reinforced composites. Interface defects with random radius and total number at the fiber‐matrix interface are modeled as an interphase between original composite components with the thickness obeying all the discontinuities and material parameters of this new, fictitious material are obtained by modified spatial averaging method. Such a model is used in the stochastic finite element analysis of composites in their original configuration. Next, the probabilistic moments of global effective properties of the entire composite are estimated, thanks to the traditional Monte Carlo simulation method implementation. Numerical experiments show that introduction of the interface defects results in significant increase of randomness level of the composite displacements and the homogenized elastic characteristics. Computer programs implemented can find their applications in digital image‐based analysis and the reliability analyses for fiber‐reinforced composites.

Effectiveness of the homogenization method for various heat transfer problems of engineering composites is the main aim of the paper. This comparative study is done for layered, fiber and particle reinforced Representative Volume Elements (RVE) for composites made of widely used components. Mathematical model is based on the effective modules method introduced for periodic composites ‐ effective heat conductivity is calculated in the closed form for specific spatial distribution of the components, while effective volumetric heat capacity is obtained from a simple spatial averaging. Such a homogenization scheme makes possible to significantly simplify the numerical analysis of transient heat transfer phenomena in various types of composites. The comparison of temperature histories obtained for the real and homogenized composite models is carried out using the Finite Element Method system ANSYS. As is demonstrated for various boundary problems, a homogenization technique in terms of composites types collected in the paper give satisfactory agreement with the real structure modeling; further numerical studies on composite cells discretization should increase modeling efficiency and diminish the numerical errors.

This paper aims to empirically examine the proposed framework that incorporates multiple business relational ties as components in a composite that can provide strength to relationships. Strength is conceptualized as tensile strength or an ability to withstand stress without permanent deformation of the relationship.

The study uses dyadic survey data collected by mail survey from the organizational buyers and suppliers. Analysis is through moderated multiple regression.

Results indicate that stressors can disrupt individual components of relationships. However, the overall relationship outcome of behavioral loyalty remains intact with tensile strength coming from other components of the relationship.

This research introduces the concept of tensile strength from the material sciences as relevant to dyadic business relationship strength. The outcomes indicate that looking at multiple components of the business relationship provides greater insight into the tensile strength of business relationships.

The purpose of this paper is to investigate the concept of new drill bit geometry adjusted to a given composite type. This paper explores the possibility of drilling in composites without negative effects such as: delamination, rapid tool wear, matrix burns, pulling out of fibers, etc.

Appropriate modification of drill bit geometries applied to composite materials include, among other things: modifications of point angles, reduction of chisel edge width, modification of drill margins and proper preparation of drill bit corners.

Description of tool geometry for drilling of different types of composites, in particular drilling in parts included free grain surfaces but also drilling at a different angle than 90°.

Geometrical details of the tool for drilling are depended on the type of composite.

Making of montage holes in parts made of composites without negative effects during drilling.

Analysis of the current state of knowledge shows that there are insufficient solutions in terms of new drill geometry for drilling of composites. Existing solutions do not guarantee adequate stability and repeatability of the cutting process. It is necessary to create new geometry drills permit the elimination of negative phenomena during drilling.

To present the findings of the research on the use of concurrent engineering in the development of polymeric based composite automotive clutch pedal. It covers the use of various IT such as expert system, FEA, CAD, mould flow and rapid prototyping in order to carry out various activities such as material selection, total design, design analysis and mould flow analysis.

The work started with the conceptual design of an automotive composite clutch pedal. Various design guides related to composite materials were followed. The final concept of the composite clutch pedal is developed using Pro/Engineer solid modelling package. Design analysis was carried out using LUSAS to study the optimum pedal lever cross section and the optimum rib patterns in pedal lever. Mould flow analysis was investigated to predict the behaviour of materials inside the injection moulding machine and the results are compared with experimental values. Rapid prototyping models were developed based on two techniques namely 3D printer and stereolithography and they are compared in terms of quality, time and cost.

In this study, the integrated IT tools enable the designer to design and manufacture automotive an composite clutch pedal at higher quality and faster time compared to a metal counterpart. By adopting composite design guides, weight saving from implementing composite materials in the clutch pedal is achievable. It is found that an expert system for material selection enables designer to select the suitable composite material for the clutch pedal by considering various parameters such as strength, modulus, density, manufacturing and economic constraints. Rapid prototyping models enable the designer to communicate effectively their design to other parties early in the design process. Mould flow analysis is carried out to predict the behaviour of material inside the mould and to design the optimum moulding parameters such as fill time, fill temperature and gate location.

In this study, the originality lies in the integration of various IT tools in the development of composite clutch pedal. The designer is exposed to various design and manufacturing issues from the implementation of such approach early in the design process.

WHEN the Harrier GR 5 begins operations, the Royal Air Force will have an aircraft of which one quarter of the structure weight is composites and one half of the structure area. Major primary structure components are fabricated from carbon fibre composites (CFC) whose characteristics are notably different from light alloys. These differences have to be taken into account when appreciating the problems of supporting such an aircraft and providing the best methods of effecting repairs to damaged structure.

The purpose of this paper is to observe the effect of cheap cow horn ash particles (CHAp) filler as a possible replacement for expensive fillers on the mechanical properties of polyester-banana peduncle fibre (BPF) composites were evaluated using standard procedures.

Composite was developed using CHAp as a filler component, polyester resin and BPF, with the filler of varying percentage weights (5%, 10%, 15% and 20%), at particle sizes of 125 µm, using hand lay-up technique. The physicochemical properties of CHAp were examined through x-ray fluorescence (XRF), X-ray diffractometer (XRD), transmission electron microscopy, scanning electron microscope, energy dispersion spectrometric analysis (EDS) and density. Mechanical properties of the developed composites were also examined.

The results showed that the tensile properties and impact strength of the composites reduced marginally with the incorporation of the cow horn ash particle as a filler. However, the flexural strength of the composites increased progressively with the incorporation of BPF as the fibre loading increased. The major constituents of CHAp were CaO from XRF study, calcite (CaCO₃) from XRD study and Ca in EDS study in accordance with the analytical parameter, which showed a major component of calcium. The high value of CaCO₃ in CHAp improved flexural and impact strengths of the composites. CHAp presented around solid and irregular shape particle characteristic of most fillers with an average particle size of 98.13 nm. The tensile and flexural strengths of the polyester matrix composites obtained at 7.5% BPF: 7.5% CHAp was 117.87 MPa depicting satisfactory mechanical characteristics.

Generally, cow horn ash particle exhibited adequate filler component potential in composite production in keeping with its property effects on the mechanical properties of polyester-BPF composites.

Details the development of composites, in particular carbon fibre reinforced plastics, for use in aerospace structures. Describes a wide range of products manufactured by various companies. Looks at the integrity of these materials and the testing methods used to ensure this. In particular, discusses metal matrix composites, aluminium/silicon carbide particulate MMCs and fibre‐metal laminates. Finally looks at advanced composites’ promise of being able to meet the needs of high specific properties and enhanced temperature capability required for future engines.

The purpose of this paper is to analyze machinability of CFRP, GFRP, GLARE-type composites in drilling process taking into account their features and properties (the geometric characteristics, the volume fraction and the mechanical properties of the individual components of the composite). Drilling in non-plan surfaces and slope drilling.

The tests were carried out in two stages: perpendicular drilling of materials such as GLARE with special drill bits, and drilling of composite structures with non-planar surfaces made of unidirectional carbon fiber prepregs, using the modified special drill. Measurement of cutting forces and torque, stress distribution (photoelastic method) and a visual assessment of defects occurring during drilling allowed to determine the relationship between the type and geometry of the composite drill.

Identified great effect of kind of composite on the machinability of these materials has substantiated modification of the standard geometry of drills and matching this geometry to specific properties of the various type of composites.

Drilling of assembly holes for aerospace parts.

New type of drill geometry for different type of composite.