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When manufacturing an arc-shaped tube product using push bending process, the transition zone and outfeed zone will inevitably occur. Transition zone and outfeed zone are caused by the kinematical motion of mobile tools. The existence of transition zone and outfeed zone will lead to a big deviation between the forming product and desired shape. To improve the forming quality of arc-shaped products in push bending, the transition zone and outfeed zone are investigated in this paper.

A piecewise function is used to describe the bending characteristics along bending line, in which a series of vibration parameters are extracted and considered as control values.

The new strategy is helpful for finding the relationship between tools motion and curvature distribution and improving the bending lines design procedure in flexible push bending.

The new strategy is helpful for finding the relationship between tools motion and curvature distribution and improving the bending lines design procedure in flexible push bending.

Bending and shear rigidities of woven fabrics depend on fibre, yarn and fabric-related parameters. However, there is lack of research efforts to understand how bending and shear rigidities change in woven fabrics having similar areal density. The purpose of this paper is to investigate the change in bending and shear rigidities in plain woven fabrics having similar areal density.

A total of 18 fabrics were woven (9 each for 100 per cent cotton and 100 per cent polyester) keeping the areal density same. Yarns of 20, 30 and 40 Ne were used in warp and weft wise directions and fabric sett was adjusted to attain the desired areal density.

When warp yarns become finer, keeping weft yarns same, bending rigidity remains unchanged but shear rigidity increases in warp wise direction. When weft yarns are made finer, keeping the warp yarns same, both the bending and shear rigidities of fabric increase in warp wise direction. Similar results for fabric bending and shear rigidities were obtained in transpose direction. There is a strong association between fabric shear rigidity and number of interlacement points per unit area of fabric even when fabric areal density is same.

Very limited research has been reported on the low-stress mechanical properties of woven fabrics having similar areal density. A novel attempt has been made in this research work to investigate the bending and shear rigidities of woven fabrics having similar areal density. Besides, it has been shown that it is possible to design a set of woven fabrics having similar bending rigidity but different shear rigidity.

Laser bending is a good candidate to replace the flame bending process. The electrochemical response of laser bending region changes due to the microstructural modifications and high level of residual stress developed in the laser‐irradiated region after the bending process. Consequently, investigation into laser bending and microstructural changes in the irradiated region as well as the electrochemical response of bending section becomes essential. This paper aims to focus on the laser bending process.

The laser bending of steel sheets was carried out. The microstructural changes in the bending region are examined using the scanning electron microscopy and X‐ray diffraction. The electrochemical response of the bended sections is investigated through potentiodynamic tests.

It is found that laser‐irradiated surface is free from cracks and cavitations. However, deep pit sites due to secondary pitting are observed in the bending sections.

The experiment is limited to certain thickness of the steel sheets. Increasing workpiece thickness reduces the bend angle. However, introducing high‐intensity laser beams improves the bend angle on the expense of high surface roughness in the bend section.

Laser bending process is involved with non‐mechanical tooling with low cost and precision of operation. Moreover, laser bending is a good candidate to replace the flame bending process. Consequently, laser bending finds application in industry. However, under the corrosive environment care should be taken.

The work presented is original and has not been published anywhere before. The findings will be useful for researchers and engineers working in the sheet metal forming area.

This paper presents the approximate limit pressure solution for shape-imperfect and through-wall circumferential cracked (TWCC) 90° pipe bends at the intrados region. Finite element (FE) limit analysis was used to estimate the limit pressure by considering the small geometrical change effects.

Three-dimensional (3D) geometric linear FE methodology was implemented to investigate the limit pressure of structurally deformed TWCC 90° pipe bends. The material considered in the analysis is elastic perfectly plastic (EPP). The limit pressure of TWCC shape-distorted pipe bends was predicted from the corresponding internal pressure when von-Mises stress was equal to or just exceeded the material’s yield strength for all the models. The theoretical solution which was published in the literature was used to evaluate the current FE approach.

Ovality C_o and TWCC at the intrados region caused a considerable impact on pipe bends, while the thinning? C_t produced a negligible effect and hence was not included in the analysis. With the combined effect, the bend portion of pipe bend experiences substantial influence, and the TWCC effect consequently increases with 45^o, 60^o and 90^o crack angles and decreases the limit pressure of pipe bends. An improved closed-form empirical limit pressure solution was proposed for TWCC shape-distorted pipe bends at the intrados region.

In the limit pressure analysis of 90° pipe bends, the implications of structural irregularities (ovality and thinning) and TWCC have not been examined and reported.

There has been much discussion in the literature about the relationship between fabric “handle” and objective instrumental measurements of fabric low stress mechanical and surface properties such as fabric tensile properties, shear, bending, lateral compression, surface friction and surface roughness. But fabric “handle” is not really an inherent fabric property, rather it is a description of one of the ways in which people generally make a subjective assessment of some of the quality attributes of apparel fabrics, designed for particular end‐use applications. In contrast, fabric drape is an inherent mechanical property of a fabric. Fabric drape is that unique property which quantifies the ability of a fabric to bend simultaneously in more than one plane. In order to exhibit the property of drape, fabrics must be able to bend and shear simultaneously, thus distinguishing textile materials from paper or thin polymer films. Develops a fundamental mechanical analysis of fabrics bending under their own weight. The equations governing the shape of an elastic fabric cantilever are solved numerically. Discusses the implications for experimental measurement of fabric bending length and fabric bending rigidity in terms of these numerical solutions with negligibly small errors. Graphically presents profiles of the draped fabric cantilever. Makes a comparison of the numerical solutions with the approximate formulae derived by F.T. Peirce.

It is important to monitor wrist four direction movements (flexion, extension, adduction and abduction) for hand healthcare, wrist rehabilitation and upper limb exercise, and so on. The purpose of this study is to develop a quadri-directional optical bending sensor that integrated wearable device technology in a smart glove to detect wrist four direction movements.

The quadri-directional optical bending sensor was designed with a microcontroller board, a Bluetooth wireless module, a side-emitting polymeric optical fibre (POF), an infrared light emitting diode and four phototransistors. A linear equation was deduced to calculate bending angle from detecting sensor value of Arduino microcontroller. The bending angle values could be seen by the smartphone screen, so the system has a good human–machine interface function.

The light emission by macro-bending of the side-emitting POFs that the transmittance of the outer side is greater than the inner. The bending POFs lateral emission phenomenon integrated with phototransistors on the edge is suitable for the development of bending sensors.

This study is to develop a novel quadri-directional optical bending sensor to replace two bi-direction sensors or four uni-direction sensors for wrist four direction movements monitoring.

TODAY'S modern aeroplanes require light weight components to satisfy the aeroplane's flight performance requirements. More than ever before new designs require commercially pure titanium (Grades A40, A55, and A70) because of the needs for high ductility associated with moderate strength, high corrosion resistance and good weld ability. Commercial aeroplane pneumatic system ducting is an excellent application of titanium material. Recently, titanium has been used in other applications on aircraft such as hydraulic and fuel piping in addition to ducting.

In the course of flexible PCB manufacture where the reliability of those parts subjected to bending stresses is a matter of utmost concern, the design of the PCB should enable the flexible interconnection parts to withstand the greatest possible bending stresses. Therefore, extensive investigations were carried out to demonstrate the relationship between the design and flexural strength. The study shows the functional correlation between bending radius, material thickness, type of material, design of the circuit and number of bending cycles. Only with a detailed knowledge of these five mentioned properties can reliable PCBs be designed and manufactured. The results of these investigations are based on a great number of bending experiments performed on a practical basis and demonstrate the numerical relation between all effects. As bending cycle results are subject to relatively high deviations, the whole problem has been investigated by means of statistical evaluation criteria.

THE work described in this paper was undertaken to investigate the behaviour of a magnesium alloy beam clastically and plastically deformed by a uniform bending moment at room temperature. The object of the work was to obtain relations between stresses and strains in the beam, to afford a basis for design, in cases where it is required to submit magnesium alloy structures to bending stresses exceeding the elastic limit.

The purpose of this study is to investigate the bending analysis of metal (Ti-6Al-4V)-ceramic (ZrO₂) functionally graded material (FGM) sandwich plate with material property gradation along length and thickness direction under thermo-mechanical loading using inverse trigonometric shear deformation theory (ITSDT). FGM sandwich plate with a ceramic core and continuous variation of material properties has been modelled using Voigt’s micro-mechanical model following the power law distribution method. The impact of bi-directional gradation of material properties over the bending response of FGM plate under thermo-mechanical loading has been investigated in this work.

In this study, gradation of material properties for FGM plates is considered along length and thickness directions using Voigt’s micromechanical model following the power law distribution method. This type of FGM is called bi-directional FGMs (BDFGM). Mechanical and thermal properties of BDFGM sandwich plates are considered temperature-dependent in the present study. ITSDT is a non-polynomial shear deformation theory which requires a smaller number of field variables for modelling of displacement function in comparison to poly-nominal shear deformation theories which lead to a reduction in the complexity of the problem. In the present study, ITSDT has been utilized to obtain the governing equations for thermo-mechanical bending of simply supported uni-directional FGM (UDFGM) and BDFGM sandwich plates. Analytical solution for bending analysis of rectangular UDFGM and BDFGM sandwich plates has been carried out using Hamilton’s principle.

The bending response of the BDFGM sandwich plate under thermo-mechanical loading has been analysed and discussed. The present study shows that centre deflection, normal stress and shear stress are significantly influenced by temperature-dependent material properties, bi-directional gradation exponents along length and thickness directions, geometrical parameters, sandwich plate layer thickness, etc. The present investigation also reveals that bi-directional FGM sandwich plates can be designed to obtain thermo-mechanical bending response with an appropriate selection of gradation exponents along length and thickness direction. Non-dimensional centre deflection of BDFGM sandwich plates decreases with increasing gradation exponents in length and thickness directions. However, the non-dimensional centre deflection of BDFGM sandwich plates increases with increasing temperature differences.

For the first time, the FGM sandwich plate with the bi-directional gradation of material properties has been considered to investigate the bending response under thermo-mechanical loading. In the literature, various polynomial shear deformation theories like first-order shear deformation theory (FSDT), third-order shear deformation theory (TSDT) and higher-order shear deformation theory (HSDT) have been utilized to obtain the governing equation for bending response under thermo-mechanical loading; however, non-polynomial shear deformation theory like ITSDT has been used for the first time to obtain the governing equation to investigate the bending response of BDFGM. The impact of bi-directional gradation and temperature-dependent material properties over centre deflection, normal stress and shear stress has been analysed and discussed.