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This paper aims to provide SIF calculation method for engineering application.

In this paper, the stress intensity factors (SIFs) calculation method is applied to the anisotropic Ni-based single crystal film cooling holes (FCHs) structure.

Based on contour integral, the anisotropic SIFs analysis finite element method (FEM) in Ni-based single crystal is proposed. The applicability and mesh independence of the method is assessed by comparing the calculated SIFs using mode of plate with an edge crack. Anisotropic SIFs can be calculated with excellent accuracy using the finite element contour integral approach. Then, the effect of crystal orientation and FCHs interference on the anisotropic SIFs is clarified. The SIFs of FCH edge crack in the [011] orientated Ni-based single crystal increases faster than the other two orientations. And the SIF of horizontal interference FCHs edge crack is also larger than that of the inclined interference one.

The SIFs of the FCH edge crack in the turbine air-cooled blade are innovatively computed using the sub-model method. Both the Mode I and II SIFs of FCHs edge crack in blade increase with crack growing.

The purpose of this paper is to discuss the chemistry of organic compounds with a liquid crystal phase and their application in flat panel electronic displays.

The paper is a review of liquid crystal display (LCD) technology. It provides an introduction to liquid crystals and LCDs, with an emphasis on their historical development, various LCD technologies employed, their electronic interconnection to driver circuitry and failure analysis.

The current world market for LCDs is being driven by flat panel television sales. As well as their use in television sets, they are to be found in aircraft cockpit instrumentation, computer monitors, mobile phones and digital cameras, all of which would not exist in their present form without liquid crystals.

The paper provides an introduction to LCDs for electronic engineers working in this area, who may be unfamiliar with the chemistry of liquid crystals, LCD technology, electronic interconnection and failure analysis.

Shape memory alloys are a fascinating class of materials because they combine both structural and functional properties. These properties strongly depend on temperature. One consequence of this dependency yields the characteristic shape‐memory effect: shape memory alloys can recover processed reference configurations after significant plastic deformations simply upon a change of temperature. For real materials, such processes incorporate characteristic hysteresis. This paper aims at an understanding of these materials from an atomistic point of view.

2D molecular‐dynamics (MD) simulations describing a chain consisting of 32 linked Lennard‐Jones crystals are presented. The crystals consist of nested lattices of two atom species. Distinct lattice structures can be identified, interpreted as austenite and (variants of) martensite. Temperature and/or load‐induced phase transitions between these configurations are observed in MD simulations. Previously, the thermal equation of state of one isolated crystal was investigated and its phase stability was discussed in detail. In the multi‐crystal chain considered in the present paper, individual crystals contribute collectively to the thermo‐mechanical behavior of the assembly.

The paper presents the results of numerical experiments with this polycrystalline chain under strain‐, load‐ and/or temperature‐control. The results show that with the assumption of simple Lennard‐Jones potentials of interaction between atoms in individual crystals and linking these crystals allows to reproduce the features associated with the fascinating behavior of shape memory alloys, including pseudo‐plasticity, pseudo‐elasticity and the shape memory effect.

Owing to the special setup chosen, interfaces are missing between adjacent crystals in the chain assembly. The paper shows that in this situation load‐induced austenite/martensite transitions do not exhibit hysteresis in tension/compression cycles. This observation indirectly supports mesoscopic‐level work in the literature which explicitly introduces interface energy to model such hysteresis.

The present paper gives an overview of the complex mathematical modelling of industrial Czochralski (CZ) and floating‐zone (FZ) processes for the growth of large silicon single crystals from melt. Extensive numerical investigations of turbulent Si‐melt flows in large diameter CZ crucibles, global thermal calculations in growth facilities and analysis of the influence of various electromagnetic fields on CZ process are presented. For FZ process, a complex system of coupled 2D and 3D mathematical models is presented to show the possibilities of modelling from the calculation of the molten zone shape till the resistivity distribution in the grown crystal. A special developed program code is presented that is used to calculate the temperature field in the crystal including radiation exchange with reflectors, stress field due to thermal expansion and shape of the dislocated zone in the case of dislocation generation. Besides the macroscopic modelling of crystal growth processes, the crystallisation model on the atomistic level in the mean field approximation is also presented.

A pseudo steady‐state model is developed to study heat transfer, fluid flow, and the interface shape in the liquid encapsulated vertical Bridgman crystal growth. The model, which is governed by momentum, heat, and overall mass balances in the system, is solved by a finite‐volume/Newton method. Flow and temperature fields, as well as unknown melt/crystal and melt/encapsulant interfaces, are calculated simultaneously. Sample calculations are mainly conducted for the GaAs/B₂O₃/PBN system. Calculated results for the Germanium/graphite system are compared with finite element calculations by Adornato and Brown, and they are in good agreement. The effects of some process parameters, including the growth speed, ambient temperature profile and heat transfer conditions, on flow patterns, temperature fields and the interface shape are illustrated through calculated results. Interface inversion from concave to convex, by modifying the ambient temperature profile, is also demonstrated through computer simulation. Particularly, through an inverse problem approach, a flat interface can be easily obtained for various operation conditions.

The purpose of this paper is to found a life model for the single crystal (SC) turbine blade based on the rate‐dependent crystallographic plasticity theory.

This life model has taken into consideration the creep and fatigue damages by the linear accumulation theory. A SC blade was taken from an aero‐engine, which had worked for 1,000 hours, as the illustration to validate the life model.

The crystallographic life model has a good prediction to the life and damage of the SC turbine blade. In the mean time, the micro damage study of the miniature specimens showed that creep damage has more serious influence on the material performance in the blade body but it is fatigue damage in the blade rabbet.

The life model can reflect the crystalline slip and deformation and crystallographic orientation of nickel‐based SC superalloys.

The purpose of this paper is to formulate an algorithm for a novel damage‐coupled material law for crystalline polyethylene at finite inelastic strains followed by investigation of the influence of the aggregate representation and material parameters on the material response.

The constitutive equations are developed within the framework of continuum damage mechanics to describe crystal fragmentation caused by atomic debonding of the crystallographic planes. The material is assumed initially isotropic and homogeneous and is represented as an aggregate of randomly oriented crystals with an orthorhombic lattice. For the velocity gradient, an additive decomposition into symmetric and skew‐symmetric components is applied, where the skew‐symmetric part (spin) is decoupled from the lattice shear by means of a damage variable. Structural features such as lattice parameters and orientations, slip systems, and kinematic constraints are incorpo‐rated.

The proposed model is implemented to predict stress‐strain behaviour under uniaxial tension and damage accumulation and texture development at the different stages of deformation. In the numerical examples, the effects of the aggregate size, crystal orientations, and material parameters on the model estimates are analyzed.

The model used herein is a first attempt to analyze the influence of crystal fragmentation caused by the debonding of the crystallographic planes on the predicted mechanical behaviour and texture development of polyethylene prior to failure.

In this paper, the authors aim to examine and comparatively evaluate a recently-developed metaheuristic called crystal structure algorithm (CryStAl) – which is inspired by the symmetries in the internal structure of crystalline solids – in solving engineering mechanics and design problems.

A total number of 20 benchmark mathematical functions are employed as test functions to evaluate the overall performance of the proposed method in handling various functions. Moreover, different classical and modern metaheuristic algorithms are selected from the optimization literature for a comparative evaluation of the performance of the proposed approach. Furthermore, five well-known mechanical design examples are utilized to examine the capability of the proposed method in dealing with challenging optimization problems.

The results of this study indicated that, in most cases, CryStAl produced more accurate outputs when compared to the other metaheuristics examined as competitors.

This paper can provide motivation and justification for the application of CryStAl to solve more complex problems in engineering design and mechanics, as well as in other branches of engineering.

CryStAl is one of the newest metaheuristic algorithms, the mathematical details of which were recently introduced and published. This is the first time that this algorithm is applied to solving engineering mechanics and design problems.

Although the use of ultrasonic agitation on quartz crystal devices during PCB cleaning has long been suspected to be detrimental, little or no data exist to substantiate or quantify the resultant effects. This paper summarises the results of a limited study into these effects for a range of quartz crystal devices, using both CFC and aqueous solvents. The variations with exposure time, and the types and mechanisms of failure are discussed. The results are encouraging and suggest that, although these devices are more susceptible to damage than ICs, once manufacturing defects have been screened out they will withstand ultrasonic exposure without deleterious effects for periods several times longer than those used for cleaning PCBs.

The purpose of this paper is to synthesise a disperse dye based on benzisothiazole and to characterise its crystal morphology, dispersing stability, to study the relationship between the chemical structure and the dyeing property of the dye.

The disperse dye based on benzisothiazole, 3-(3-methyl-4-N-ethyl-N-benzyl-phenyldiazenyl)-5-nitro-2,1-benzisothiazoles, was synthesized. The disperse dye based on benzisothiazole, 3-(3-methyl-4-N-ethyl-N-benzyl-phenyldiazenyl)-5-nitro-2,1-benzisothiazoles, was synthesised. The chemical structure of the dye obtained was characterised by infrared spectrum Fourier transform infrared spectroscopy and nuclear magnetic resonance (1HNMR), and the crystal morphology was observed by Field Emission Scanning Electron Microscopy. Sodium salt of polycondensated naphthalenesulphonic acid (dispersing agent sodium salt of polycondensated naphthalenesulphonic acid [MF]) and a sulphonated amino polyether (anionic surfactant B600) were employed to grind and disperse the dye crystals. The dispersion property of the dye particles was characterised. Dyeing property of the dispersion system was also studied.

The dye formed spherical crystals that were made up of a large number of acicular crystals similar to spherical chrysanthemum. The crystals had warping crystal centres inside the spheres. The particle sizes of the dispersion with the mixture of B600 and MF had an uniform distribution and were smaller than that of the dispersion with only single dispersing agent MF. Dyeing with the dispersion system had an excellent reproducibility under alkalinic condition.

An alkalinic dyeing method for poly(ethylene terephthalate) (PET) with disperse dyes as a cleaner wet process had been developed. Such a process combined pretreatment and dyeing process using the alkali-stable disperse dyes and reduced the consumption of water and energy and improved production efficiency.

The crystal morphology, dispersion and dyeing properties of the synthesised disperse dye for dyeing PET fabric under alkalinic condition were discussed. This disperse dye has an important potential application in alkalinic dyeing method.