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Article
Publication date: 3 November 2014

Min Li, Kaili Song, Kongliang Xie and Aiqin Hou

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 43 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 27 June 2018

Junjie Wu, Xiang Xu, Zhihao Zhao, Minjie Wang and Jie Zhang

The purpose of this paper is to investigate the effect of selective laser sintering (SLS) method on morphology and performance of polyamide 12.

Abstract

Purpose

The purpose of this paper is to investigate the effect of selective laser sintering (SLS) method on morphology and performance of polyamide 12.

Design/methodology/approach

Crystallization behavior is critical to the properties of semi-crystalline polymers. The crystallization condition of SLS process is much different from others. The morphology of polyamide 12 produced by SLS technology was investigated using scanning electron microscopy, polarized light microscopy, differential scanning calorimetry, X-ray diffraction and wide-angle X-ray diffraction.

Findings

Too low fill laser power brought about bad fusion of powders, while too high energy input resulted in bad performance due to chain scission of macromolecules. There were three types of crystal in the raw powder material, denoted as overgrowth crystal, ring-banded spherulite and normal spherulite.

Originality/value

In this work, SLS samples with different sintering parameters, as well as compression molding sample for the purpose of comparison, were made to study the morphology and crystal structure of sintered PA12 in detail.

Details

Rapid Prototyping Journal, vol. 24 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 20 August 2019

Merlina A. Navarro Villanueva, Luis A. Soto Hernández, Melquisedec Vicente Mendoza, Ángel de J. Morales Ramírez and Fernando Juárez López

This paper aims to study the microstructural hot corrosion behaviour of the sintered Y2SiO5 ceramic silicate under a Na2SO4 + V2O5 mixture at an engine representative…

Abstract

Purpose

This paper aims to study the microstructural hot corrosion behaviour of the sintered Y2SiO5 ceramic silicate under a Na2SO4 + V2O5 mixture at an engine representative temperature of 1150°C. Y2SiO5 is a promising candidate for thermal barrier coatings (TBC) due to its excellent chemical stability at high temperatures. As a continuous source of Y3+, it is expected that Y2SiO5 environmental barrier coating may prolong the lifetime of TBC systems by stopping the degradation caused by the loss of the Y2O3 stabilizer.

Design/methodology/approach

Two routes were chosen for the yttria silicate powder synthesis by sol-gel from TEOS and APTES precursors as the difference in Si source changed the ratio of Y2SiO5/Y2Si2O7 phases. Hot corrosion studies using Na2SO4 and V2O5 mixtures were conducted on both surfaces of APTES and TEOS tablets at 1150°C for 8 h in atmospheric air. The morphology and microstructure analyses of the silicate samples after hot corrosion tests were carried out using a SEM and X-ray diffraction analyse techniques.

Findings

Based on the degradation, the general status of the APTES tablet after hot corrosion presents a better hot corrosion resistance at a temperature of 1150°C than does that of the TEOS tablet. In the TEOS tablet, the crystal morphology of NaY9Si60O26 woodchip shapes with a size of 60 µm is developed on the surface for finally initiating some cracks. In the APTES case, the crystal morphology of rod-like shapes with a size of 100 µm is developed; hence, a dense thick layer predominately postpones the reaction of V2O5 and Na2SO4 with yttria silicate, and consequently, less damage is observed.

Originality/value

Coating yttria silicate preparation is very complicated; the problems of a high synthesis temperature, long production period and low yield still need to be solved. Under these perspectives, ceramics prepared via spark plasma sintering (SPS) can reach theoretical high densities and a fine grain size can be retained after the SPS process; hence, well resistance to the corrosion in molten salts is expected to obtain for the sintered yttria silicate tablets.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 6 August 2019

Jieren Guan, Xiaowei Zhang, Yehua Jiang and Yongnian Yan

This study aims to obtain the mechanistic insights for the fabrication of pure copper thin wall components by selective infrared (IR) laser melting (SLM) and correlated…

Abstract

Purpose

This study aims to obtain the mechanistic insights for the fabrication of pure copper thin wall components by selective infrared (IR) laser melting (SLM) and correlated with microstructure development, microhardness, surface morphology and phase analysis. Experimental processes for single track and selection of substrate materials have been studied using a combination of different laser powers and scanning speeds.

Design/methodology/approach

SLM of pure copper was performed on a YONGNIAN Laser YLMS-120 SLM machine using an Nd: YAG fiber laser operating at 1,060 nm in the NIR region. Single-track experiments and processing parameters are investigated through different combinations of laser power and scanning speed. The microstructure of the fabricated pure copper samples by SLM technique was analyzed by means of X-ray diffraction, scanning electron microscope equipped with energy disperse spectrometer, optical microscope (OM) and micro-hardness tester.

Findings

Steel-based substrates were found suitable for pure copper manufacturing due to sufficient heat accumulation. The width of a single track was determined by liner energy density, showing discontinuities and irregular morphologies at low laser powers and high scanning speeds. As a result of instability of the molten pool induced by Marangoni convection, cracks and cavities were observed to appear along grain boundaries in the microstructure. The top surface morphology of SLM-processed component showed a streamflow structure and irregular shapes. However, the powder particles attached to side surface, which manifest copper powders, are even more sensitive to melt pool of contour track. The crystal phase characteristics of copper components indicated increasing crystallite size of a-Cu, and the decreasing intensity of diffraction peak was attributed to the presence of defects during SLM. The maximum relative density and microhardness were 82 per cent and 61.48 HV0.2, respectively. The minimum thickness of a pure copper thin wall component was 0.2 mm.

Originality/value

This paper demonstrated the forming mechanism and explored feasibility of pure copper thin wall parts by SLM technology in the NIR region. The surface morphology, microstructure and crystal structure were preliminary studied with laser processing parameters.

Details

Rapid Prototyping Journal, vol. 25 no. 8
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 6 March 2017

Xinmin Huang, Lingling Meng, Qufu Wei, Qianwen Wang and He Zhang

The purpose of this paper is to discuss polyester fabric structures in terms of the surface morphology, crystal structure of copper films and interfacial bonding…

Abstract

Purpose

The purpose of this paper is to discuss polyester fabric structures in terms of the surface morphology, crystal structure of copper films and interfacial bonding properties between polyester fabrics and copper films.

Design/methodology/approach

Nanoscale copper (Cu) thin films were deposited onto the surface of polyester fabrics with different structures by the radio frequency magnetron sputtering technique at room temperature.

Findings

Copper films uniformly deposited on the surface of the polyester nonwovens and nanofiber membranes have larger average particle diameters and surface roughness, and higher crystallinity.

Originality/value

Theoretical value: the effects of polyester substrate structures on the morphology and interfacial bonding properties of Cu thin films have rarely been reported.

Details

International Journal of Clothing Science and Technology, vol. 29 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

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Article
Publication date: 9 July 2020

G.I. Yakovlev, A. Gordina, Rostislav Drochytka, A.F. Buryanov and Olga Smirnova

The purpose of the study is regarding the development of eco-oriented technologies for obtaining the building gypsum materials with the involvement of industrial…

Abstract

Purpose

The purpose of the study is regarding the development of eco-oriented technologies for obtaining the building gypsum materials with the involvement of industrial by-products or waste.

Design/methodology/approach

The scanning electron microscopy, X-ray microanalysis and IR spectral analysis were used to study the structure of gypsum matrix. The method of comparison of modified and unmodified gypsum matrix was used. Physical modeling of gypsum matrix crystallization is used to study changes in the morphology of hydration products.

Findings

The experimental results show that the addition of technical soot into a gypsum binder leads to a change in the morphology of crystalline hydrates of calcium sulfate dihydrate. Results of the scanning electron microscopy, X-ray microanalysis and IR spectral analysis confirm the change of physical and mechanical characteristics of the gypsum binder due to the structural modification of the gypsum matrix with ultrafine carbon soot. The achieved degree of the structural modification of the gypsum matrix is compatible with the results obtained when the gypsum binder was modified with dispersions of carbon nanotubes.

Originality/value

The morphology of the crystalline hydrates of the gypsum matrix with the addition of 0.04%, 0.06% and 1% of the carbon soot is characterized by the transition of the classical needle-like structure of gypsum dihydrate to the lamellar structure of increased density. One can observe the formation of intergrowths around ultrafine carbon soot particles. The studied carbon additive can improve strength characteristics of the gypsum matrix.

Details

Smart and Sustainable Built Environment, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2046-6099

Keywords

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Article
Publication date: 12 November 2020

Abid Ullah, HengAn Wu, Asif Ur Rehman, YinBo Zhu, Tingting Liu and Kai Zhang

The purpose of this paper is to eliminate Part defects and enrich additive manufacturing of ceramics. Laser powder bed fusion (L-PBF) experiments were carried to…

Abstract

Purpose

The purpose of this paper is to eliminate Part defects and enrich additive manufacturing of ceramics. Laser powder bed fusion (L-PBF) experiments were carried to investigate the effects of laser parameters and selective oxidation of Titanium (mixed with TiO2) on the microstructure, surface quality and melting state of Titania. The causes of several L-PBF parts defects were thoroughly analyzed.

Design/methodology/approach

Laser power and scanning speed were varied within a specific range (50–125 W and 170–200 mm/s, respectively). Furthermore, varying loads of Ti (1%, 3%, 5% and 15%) were mixed with TiO2, which was selectively oxidized with laser beam in the presence of oxygen environment.

Findings

Part defects such as cracks, pores and uneven grains growth were widely reduced in TiO2 L-PBF specimens. Increasing the laser power and decreasing the scanning speed shown significant improvements in the surface morphology of TiO2 ceramics. The amount of Ti material was fully melted and simultaneously changed into TiO2 by the application of the laser beam. The selective oxidation of Ti material also improved the melting condition, microstructure and surface quality of the specimens.

Originality/value

TiO2 ceramic specimens were produced through L-PBF process. Increasing the laser power and decreasing the scanning speed is an effective way to sufficiently melt the powders and reduce parts defects. Selective oxidation of Ti by a high power laser beam approach was used to improve the manufacturability of TiO2 specimens.

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Article
Publication date: 1 August 2002

J.G. Lee, F. Guo, K.N. Subramanian and J.P. Lucas

The influence of the thermal reflow profile on the formation and resultant morphology of the intermetallic layer that developed at the Ni particle reinforcements within an…

Abstract

The influence of the thermal reflow profile on the formation and resultant morphology of the intermetallic layer that developed at the Ni particle reinforcements within an eutectic Sn‐Ag composite solder matrix was investigated. The composite solder was fabricated by mechanically dispersing 15 vol% Ni particles into eutectic Sn‐3.5Ag solder paste. Two distinct intermetallic compound (IMC) morphological microstructures were observed around the Ni reinforcements. IMC morphological microstructure apparently varied depending on the amount of heat input and differences in heating rates used in the reflow profile. A “sunflower” IMC morphology was typically noted when the total amount of heat input was small. However, with sufficient heat input, a faceted “blocky” IMC morphology was consistently achieved. Multiple‐reflow thermal profiling experiments were conducted to measure and compare the amount of heat input necessary to change the sunflower IMC morphology around Ni particle reinforcements to the blocky morphology.

Details

Soldering & Surface Mount Technology, vol. 14 no. 2
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 28 April 2020

Lingling Meng, Xinmin Huang, Qufu Wei, Dandan Ji and Qianwen Wang

The paper aims to evaluate the influence of atmospheric environment on the conductivity of nanoscale copper films sputtered on polyester substrates; process parameters of…

Abstract

Purpose

The paper aims to evaluate the influence of atmospheric environment on the conductivity of nanoscale copper films sputtered on polyester substrates; process parameters of optimal conductivity were firstly analyzed by orthogonal test scheme design, and then the surface morphology, crystal structures and conductivity of samples were performed after samples were placed in the atmospheric conditions for some time according to the optimization of process parameters.

Design/methodology/approach

Nanoscale copper films was prepared by RF (radio frequency) magnetron sputtering and low-temperature plasma technology with polyester fabrics as substrates and metal copper as targets under the conditions of low temperature and high vacuum.

Findings

The experimental results showed that copper films were broken and the continuity of samples was destroyed after 60 days, while exposed in atmospheric environment for 90 days, cracks of copper films gradually expanded, there was no change in the atomic species for samples placed in the atmospheric conditions. However, the conductivity of the samples hardly had changed with the ambient temperature, humidity and degree of water washing, which is mainly decided by the internal structures of substrates.

Originality/value

This paper has some theoretical and applicable value to the functional textile.

Details

International Journal of Clothing Science and Technology, vol. 32 no. 5
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 20 January 2012

Yidong Zhang and Weiwei He

The purpose of this paper is to demonstrate the I‐V characteristics of ZnO film on Si substrates with Ag buffer layer by conductive atomic force (C‐AFM).

Abstract

Purpose

The purpose of this paper is to demonstrate the I‐V characteristics of ZnO film on Si substrates with Ag buffer layer by conductive atomic force (C‐AFM).

Design/methodology/approach

An Ag buffer layer and Zn film was first deposited on silicon substrate by RF‐sputtering deposition method from high pure Ag and Zn target, respectively. Then, the deposited film was sintered in air at 500°C for 1 h.

Findings

The structures and morphologies of the prepared films were characterized by X‐ray diffraction (XRD), energy dispersive spectrum (EDS), atomic force microscopy (AFM), and C‐AFM. The results show that the prepared ZnO films with Ag buffer layer have a good crystallinity and surface morphology. Interestingly, the I‐V curve of ZnO film exhibited typical characteristics of semi‐conductive oxide under the conductive Ag buffer layer.

Originality/value

The paper demonstrates, by C‐AFM, that the ZnO/Ag‐buffer/Si exhibits excellent crystal structure, morphology and typical I‐V characteristics.

Details

Microelectronics International, vol. 29 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

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