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In this work, the changes to stereolithography (SL) resin mechanical properties during the injection moulding process were evaluated. A multi‐impression SL mould was built and used to inject a series of small flat mouldings. The fixed half SL tool insert included recesses to accommodate tensile test specimens. Tensile test specimens made from SL resin were positioned in these recesses and plastic parts were injected. After injecting a predetermined number of mouldings, tensile tests were performed using the tensile test specimens. The results from the tensile tests show that the thermal cycling encountered during the injection moulding process did not significantly affect the mechanical properties of the resin. Observations indicate that decrease in the temperatures encountered in the tool may lead to longer tool life.

Lattice Boltzmann method (LBM) has made great success in computational fluid dynamics, and this paper aims to establish an efficient simulation model for the polymer injection molding process using the LBM. The study aims to validate the capacity of the model for accurately predicting the injection molding process, to demonstrate the superior numerical efficiency in comparison with the current model based on the finite volume method (FVM).

The study adopts the stable multi-relaxation-time scheme of LBM to model the non-Newtonian polymer flow during the filling process. The volume of fluid method is naturally integrated to track the movement of the melt front. Additionally, a novel fractional-step thermal LBM is used to solve the convection-diffusion equation of the temperature field evolution, which is of high Peclet number. Through various simulation cases, the accuracy and stability of the present model are validated, and the higher numerical efficiency verified in comparison with the current FVM-based model.

The paper provides an efficient alternative to the current models in the simulation of polymer injection molding. Through the test cases, the model presented in this paper accurately predicts the filling process and successfully reproduces several characteristic phenomena of injection molding. Moreover, compared with the popular FVM-based models, the present model shows superior numerical efficiency, more fit for the future trend of parallel computing.

Limited by the authors’ hardware resources, the programs of the present model and the FVM-based model are run on parallel up to 12 threads, which is adequate for most simulations of polymer injection molding. Through the tests, the present model has demonstrated the better numerical efficiency, and it is recommended for the researcher to investigate the parallel performance on even larger-scale parallel computing, with more threads.

To the authors’ knowledge, it is for the first time that the lattice Boltzmann method is applied in the simulation of injection molding, and the proposed model does obviously better in numerical efficiency than the current popular FVM-based models.

To provide a systematic framework for mold designers, that can be used for rapid tooling (RT) process selection and prioritization of process parameters.

This paper presents a QFD‐AHP methodology which has three phases. The first phase involves prioritizing the tooling requirements (driven by customer preferences) against a set of die/mold development attributes (such as product material, geometry, and die material and production order) through pair‐wise comparison using analytical hierarchal process (AHP). These priority ratings are used for selecting the most appropriate tooling process using quality function deployment (QFD) in the second phase. Finally, QFD is used again for identifying critical process parameters (such as layer thickness, scan pitch and laser power) for the selected RT process.

The QFD‐AHP methodology has been illustrated with industrial examples on RT for molded parts. The molds were fabricated using direct metal laser sintering and spray metal tooling processes, for example, 1 and 2, respectively, to prove that the methodology can be easily implemented in tool rooms. The issues noted in these experimental studies are also discussed for the benefit of researchers.

The capabilities of the RT processes presented in the paper reflect the experience of the research team in RT development. The QFD‐AHP methodology will give progressively better results with a growing body of RT process knowledge.

This investigation is a key step towards the goal of developing a comprehensive system for RT process selection and manufacturability evaluation. The mold designer can use this QFD‐AHP process selection methodology, prior to detailed manufacturability analysis, to better realize the benefits of RT technologies.

The proposed QFD‐AHP methodology is a new approach for the tooling process selection domain, and has not been reported earlier; this can be easily used for similar applications for any manufacturing domain.

This study aims to investigate the mechanical, thermal, melt-flow and morphological behavior of acrylonitrile-butadiene-styrene (ABS)-based composites after bentonite inclusions. Melt mixing is the most preferred production method in industrial scale and basically it has very near processing parameters compared to 3D printing applications. Rheological parameters of ABS and its composites are important for 3D applications. Melt flow behavior of ABS effects the fabrication of 3D printed product at desired levels. Shear thinning and non-Newtonian viscosity characteristics of ABS make viscosity control easier and more flexible for several processing techniques including injection molding, compression molding and 3D printing.

ABS copolymer was reinforced with bentonite mineral (BNT) at four different loading ratios of 5%, 10%, 15% and 20%. ABS/BNT composites were fabricated by lab-scale micro-compounder followed by injection molding process. Mechanical, thermo-mechanical, thermal, melt-flow and morphological properties of composites were investigated by tensile, hardness and impact tests, dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA), melt flow index (MFI) test and scanning electron microscopy (SEM), respectively.

Mechanical tests revealed that tensile strength, elongation and hardness of ABS were enhanced as BNT content increased. Glass transition temperature and storage modulus of ABS exhibited increasing trend with the additions of BNT. However, impact strength values dropped down with BNT inclusion. According to MFI test measurements, BNT incorporation displayed no significant change for MFI value of ABS. Homogeneous dispersion of BNT particles into ABS phase was deduced from SEM micrographs of composites. Loading ratio of 15% BNT was remarked as the most suitable candidate among fabricated ABS-based composites according to findings.

The advanced mechanical properties and easy processing characteristics are the reasons for usage of ABS as an engineering plastic. Owing to the increase in its usage for 3D printing technology, the ABS became popular in recent years. The utilization of ABS in this technology is in filament form with various colors and dimensions. This is because of its proper rheological features.

Melt-mixing technique was used as preparation of composites, as this processing method is widely applied in industry. This method is also providing similar processing methodology with 3D printing technology.

According to the literature survey, to the best of the authors’ knowledge, this study is the first research work regarding the melt-flow performance of ABS-based composites to evaluate their 3D printing applications and processability. ABS and BNT containing composites were characterized by tensile, impact and shore hardness tests, DMA, TGA), MFI test and SEM techniques.

On May 24, 2019, the People’s Bank of China (China’s central bank) announced that the Baoshang Bank had been taken over because of credit risk. The Baoshang Bank failure has caused concerns over the stability of the Chinese financial system and the Chinese economy. This study aims to examine the case of Baoshang Bank’s failure and its theoretical implications including the relation between ownership structure and bank performance, the monetary transmission during a banking crisis and the market response to Baoshang Bank failure. Then this study discusses policy implications.

This study adopts a two-stage least squared model to examine the relation between ownership structure and bank performance, a series of rolling regressions to examine the monetary transmission and event studies to examine the market response to Baoshang Bank failure.

This study finds that there is a nonlinear relation between ownership structure and bank performance, the interest pass-through has broken down after the Baoshang Bank failure and the Baoshang Bank failure and the gradual exit of implicit guarantee from the Chinese government are considered to be positive to the Chinese banking sector.

First, although previous studies on ownership structure and bank performance classified different types of larger shareholders and found that this nonlinear relation is insignificant, this study finds a significant relation by innovatively using a combined ownership. Second, further contributing to the studies on monetary transmission in banking crisis based on international data, this study based on Chinese data sets finds that the interest rate pass-through has broken down after the Baoshang Bank failure.

Describes the developments of a small, robust ultrasonic wind speed and direction indicator. Gill’s patented ultrasonic technology is based on the time‐of‐flight operating principle, which provides vector measurement of air velocity, given the dimensions and geometry of pairs of transducers. In this case, two pairs of transducers are used such that the air velocity can be derived along orthogonal axes and hence the air speed and direction can be computed.

EVEN IN THE CASE OF THE MOST MODERN MILLS equipped with the latest lubrication installations, little attempt has been made to lubricate the palm ends of intermediate spindles. The importance of good lubrication of palm ends is underlined by the fact that there is constant sliding friction of a reciprocating nature. The wear on palm ends and bushes is usually considerable. Some steel mill manufacturers have tried to overcome the difficulty by using a spring loaded lubricator, but this is only partially successful. A solution is provided by the Centralube Palm End Lubricator, supplied by Centralube Ltd., Great Western Trading Estate, Park Royal Road, London, N.W.10.