Search results

1 – 10 of over 3000
To view the access options for this content please click here
Article

Ramakrishnan G., Prakash C. and Janani G.

The purpose of this paper is to investigate plasma treatment for Tencel microfibre fabrics for possible improvement in various functional properties.

Abstract

Purpose

The purpose of this paper is to investigate plasma treatment for Tencel microfibre fabrics for possible improvement in various functional properties.

Design/methodology/approach

The plasma treated and untreated fabrics were dyed using reactive dyes and evaluated for comfort properties such as wicking, water vapour permeability and air permeability.

Findings

The various comfort properties of plasma treated and an untreated Tencel microfibre fabric have been studied. The wicking results showed a significant reduction in wicking time for plasma treated fabrics compared to untreated fabrics. The test results for water vapour permeability show no significant difference between plasma treated and untreated fabrics. The plasma treated samples show higher air permeability than untreated samples. In the wetting test, it is clearly seen that the plasma treated samples absorbed the water at a faster rate.

Originality/value

This research investigates plasma treatment for Tencel microfibre fabrics for possible improvement in various functional properties.

Details

International Journal of Clothing Science and Technology, vol. 30 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

To view the access options for this content please click here
Article

Bengi Kilic, Aysun Cireli Aksit and Mehmet Mutlu

Plasma polymerization is a very promising technique to produce functional textile materials for any textile end uses as well as for high performance clothing. It can be…

Abstract

Purpose

Plasma polymerization is a very promising technique to produce functional textile materials for any textile end uses as well as for high performance clothing. It can be possible to obtain highly cross‐linked, pinhole free and very thin polymer films up to 1 μm thickness with unique physical and chemical properties. These films can be used as very effective barriers. The purpose of this paper is to investigate the influences of plasma polymerization of hexamethyldisilane (HMDS) and hexamethyldisiloxane (HMDSO) on the surface properties of cotton and polyamide fabrics.

Design/methodology/approach

The methodology is based on the surface modification of the cotton and polyamide fabrics by plasma polymerization of HMDS and HMDSO. The fabrics are modified by low pressure low temperature RF (radio frequency −13.56 MHz) plasma polymerization system under different power and time conditions. The changes in surface structure and morphology of the fabrics are investigated by Fourier transform infrared spectroscopy‐attenuated total reflectance (FTIR‐ATR) analysis and atomic force microscopy (AFM).

Findings

Water repellency of polyamide fabrics is strongly enhanced after plasma polymerization of both HMDS and HMDSO monomers. In addition to this, the treatments are found to slow down the vertical flame spread in cotton fabrics.

Originality/value

Increased water repellency and decreased vertical flame spread are achieved using plasma polymerization technique in a very short time with very little amount of chemical and without water and auxiliary agent.

Details

International Journal of Clothing Science and Technology, vol. 21 no. 2/3
Type: Research Article
ISSN: 0955-6222

Keywords

To view the access options for this content please click here
Article

Dai Cheng, Haihong Zhu and Linda Ke

This paper aimed to investigate the plasma characteristics of selective laser micro sintering Cu‐based metal powder using spectra method.

Abstract

Purpose

This paper aimed to investigate the plasma characteristics of selective laser micro sintering Cu‐based metal powder using spectra method.

Design/methodology/approach

Temporal and time integrating plasma induced during selective laser micro sintering Cu‐based metal powder with a Q‐switched pulsed YAG laser have been detected and analyzed. Boltzmann plot and Stark broadening of the spectra line are utilized to analyze the electron temperature and density, respectively. The influences of the Q‐switching rate and duration on the plasma temperature and electron density have been investigated.

Findings

The results show that the plasma temperature decreases from 9,600 to 9,000 K with the increase of the Q‐switching rate from 5 to 35 kHz if Q‐switching duration of laser is kept at a constant value. The plots of temporal temperature and electron density show that the electron density varies in a faster speed than plasma temperature and the entire expansion process takes about 700 ns‐1 μs in this experiment. Evolutional images of the plasma plume using Q‐switching rate of 5 kHz and 5 μs have been registered by the ICCD with a 10 ns exposure time, which shows that the plasma plume takes about 100 ns to get to the maximum size and 600 ns to disperse.

Originality/value

The plasma spectra of selective laser micro sintering Cu‐based metal powder have been diagnosed experimentally. The plasma characteristics of selective laser micro sintering Cu‐based metal powder have been analyzed.

Details

Rapid Prototyping Journal, vol. 19 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

To view the access options for this content please click here
Article

P. Bettini, A. Formisano, R. Martone, F. Trevisan and A. Stella

The identification of plasma parameters from different sets of measurements is a key topic in the thermonuclear fusion research. Most of the information relevant to the…

Abstract

The identification of plasma parameters from different sets of measurements is a key topic in the thermonuclear fusion research. Most of the information relevant to the plasma shape and position control is usually gained via external magnetic measurements, but information related to internal distribution of current density is not accessible in this way. Other possible measurements are available. In this paper a performance analysis is done with respect to the adoption of polarimetric measurements.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 20 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

To view the access options for this content please click here
Article

Julie Bénech, Pierre Freton, Jean‐Jacques Gonzalez and Mathieu Masquère

The purpose of this paper is to develop a mathematical tool and an experimental platform to be able to reconstruct thermal plasmas in three dimensions (3D) in order to…

Abstract

Purpose

The purpose of this paper is to develop a mathematical tool and an experimental platform to be able to reconstruct thermal plasmas in three dimensions (3D) in order to characterize 3D plasma and to validate models in 3D. Indeed, a lack of experimental data allowing validating 3D models exists.

Design/methodology/approach

The paper is realized with a transferred argon arc configuration. The 3D character is due to the form of the cathode electrode. The reactor design is defined by a previous theoretical study. This previous paper has shown that tomographic method through four views allows reconstructing 3D object. The light emitted by the plasma along four directions (four windows) is so spectrally resolved and treated by a multiplicative algebraic reconstruction technique algorithm. Following the emissivity profiles, two methods are used, the absolute line intensity method, and for an out off‐axis maximum of the emissivity the Folwer Milne method.

Findings

After a validating approach of the optical measurements in symmetrical configuration using Abel inversion, the reconstructed method is used. The results show the possibility of the tomographic method spectrally and spatially resolved to be applied to thermal plasma in order to characterise the medium and to validate the 3D models. The plasma medium is well described with a spatial resolution equal to 0.2 mm.

Research limitations/implications

The method is applicable to thermal plasma presenting high emissivity. Even if the theoretical reconstruction method is applied to low temperatures or to theoretical plasma presenting out off‐axis of emissivity, future researches need to be performed to analyse the ability of the method to spatially resolve the areas presenting low emissivity.

Originality/value

The paper's originality can be demonstrated by the poor number of studies in thermal plasma reconstruction in 3D. Studies on plasma imaging can be found but not spectrally resolved. The special care on the spectral acquisition along the plasma radius combined with the tomographic reconstruction method lead to the originality of this paper.

Details

Sensor Review, vol. 29 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

To view the access options for this content please click here
Article

A. Calahorra, S. Sali, Z. Hamish and H. Dodiuk

Peel adhesion of an epoxy filleting compound and Parylene C conformal coating to plasma treated, solder mask coated substrates and the apparent contact angle of water on…

Abstract

Peel adhesion of an epoxy filleting compound and Parylene C conformal coating to plasma treated, solder mask coated substrates and the apparent contact angle of water on the treated surfaces were evaluated. No significant improvement was achieved in the case of the epoxy filleting adhesive for most solder mask coatings studied. On the other hand, Parylene C peel adhesion significantly increased after substrates were treated with air plasma and reached the level of Silane coupling agent primed substrates. This was in contrast to the decrease in Parylene adhesion to argon plasma treated substrates in comparison with the non‐treated substrates. This was related to the oxygen functionalities created on the surfaces by the air plasma versus the ablative nature of the argon plasma. No clear correlation was found between peel strength and the water contact angle in the case of the epoxy adhesive, while for the Parylene conformal coating peel strength achieved its maximum value at the middle of the contact angle range which resulted from the pretreatments applied in this study. It is concluded that air plasma is a very efficient solder mask pretreatment for Parylene conformal coating that can replace Silane primer. Also, if a calibration curve is established for each solder mask‐adhesive and solder mask‐coating system, the apparent water contact angle can serve as a convenient quality control tool for printed circuit finishing processes.

Details

Circuit World, vol. 15 no. 3
Type: Research Article
ISSN: 0305-6120

To view the access options for this content please click here
Article

Ali Kaveh, Hossein Akbari and Seyed Milad Hosseini

This paper aims to present a new physically inspired meta-heuristic algorithm, which is called Plasma Generation Optimization (PGO). To evaluate the performance and…

Abstract

Purpose

This paper aims to present a new physically inspired meta-heuristic algorithm, which is called Plasma Generation Optimization (PGO). To evaluate the performance and capability of the proposed method in comparison to other optimization methods, two sets of test problems consisting of 13 constrained benchmark functions and 6 benchmark trusses are investigated numerically. The results indicate that the performance of the proposed method is competitive with other considered state-of-the-art optimization methods.

Design/methodology/approach

In this paper, a new physically-based metaheuristic algorithm called plasma generation optimization (PGO) algorithm is developed for solving constrained optimization problems. PGO is a population-based optimizer inspired by the process of plasma generation. In the proposed algorithm, each agent is considered as an electron. Movement of electrons and changing their energy levels are based on simulating excitation, de-excitation and ionization processes occurring through the plasma generation. In the proposed PGO, the global optimum is obtained when plasma is generated with the highest degree of ionization.

Findings

A new physically-based metaheuristic algorithm called the PGO algorithm is developed that is inspired from the process of plasma generation.

Originality/value

The results indicate that the performance of the proposed method is competitive with other state-of-the-art methods.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article

Amjed Javid, Awais Irshad, Munir Ashraf, Abdur Rehman, Shagufta Riaz and Kashif Iqbal

This paper aims to evaluate the effect of plasma treatment on the performance and color strength of pigment printed polypropylene nonwovens fabrics.

Abstract

Purpose

This paper aims to evaluate the effect of plasma treatment on the performance and color strength of pigment printed polypropylene nonwovens fabrics.

Design/methodology/approach

Melt spun nonwoven fabrics have been treated with plasma discharge using oxygen as a reactive gas to activate their surfaces for better interfacial interactions. The untreated and plasma treated fabrics are printed using pigment print pastes to investigate the print properties of nonwoven fabrics that are correlated to surface characteristics. The printed fabrics are characterized through FTIR, color fastness to washing and rubbing, flexural rigidity and moisture management observations.

Findings

The fabrics treated with oxygen plasma exhibited higher wettability, higher overall moisture management capability, enhanced color strength and superior color fastness to washing. However, bending length and flexural rigidity have been increased.

Originality/value

This study offers promising findings regarding the surface activation of polypropylene nonwovens for enhanced performance, comfort and color fastness characteristics.

Details

Pigment & Resin Technology, vol. 49 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

To view the access options for this content please click here
Article

Aminoddin Haji

The dyeing of cellulosic and proteinous fibers with natural and synthetic colorants usually needs large amounts of metal salts to promote the dyeing procedure. To get rid…

Abstract

Purpose

The dyeing of cellulosic and proteinous fibers with natural and synthetic colorants usually needs large amounts of metal salts to promote the dyeing procedure. To get rid of the necessity to use metal salts, plasma treatment and subsequent attachment of chitosan biopolymer were considered as green processes for surface functionalization of wool and cotton. The purpose of this paper is to investigate the effect of oxygen plasma treatment and attachment of chitosan on the dyeability of wool and cotton fabrics using walnut and weld as model natural dyes, as well as C.I. reactive blue 50 and C.I. acid blue 92 as model synthetic dyes.

Design/methodology/approach

Wool and cotton fabrics were modified with oxygen plasma and coated with chitosan solution. The un-modified and modified samples were dyed with the above-mentioned dyes under constant conditions. The color strength, color coordinates and fastness properties of the dyed samples were determined and compared.

Findings

The results showed that oxygen plasma treatment could improve the dyeability and fastness properties of wool and cotton fibers when dyed with all of the above-mentioned dyes. Attachment of chitosan to the plasma-treated samples significantly improved the dyeability of wool and cotton fibers with walnut, acid and reactive dyes. The fastness properties of the dyed samples were enhanced by plasma treatment and chitosan coating.

Originality/value

This study uses plasma treatment as an environmentally friendly pre-treatment for attachment of chitosan on wool and cotton. This process improved the dyeing properties of both fibers. The use of metal salts in not needed for dyeing of wool and cotton according to the investigated process.

Details

Pigment & Resin Technology, vol. 49 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

To view the access options for this content please click here
Article

Y.S. Lin, W.J. Lin and L.Y. Chiu

The purpose of this paper is to investigate the effects of H2 flow rate on improving the solder wettability of oxidized‐copper with liquid lead‐free solder…

Abstract

Purpose

The purpose of this paper is to investigate the effects of H2 flow rate on improving the solder wettability of oxidized‐copper with liquid lead‐free solder (96.5Sn‐3Ag‐0.5Cu) by Ar‐H2 plasmas. The aim was to improve the solder wettability of oxidized copper from 0 per cent wetting of copper oxidized in air at 260oC for 1 hour to 100 per cent wetting of oxidized‐copper modified by Ar‐H2 plasmas at certain H2 flow rates and to find correlations between the surface characteristics of copper and the solder wettability with liquid lead‐free solder.

Design/methodology/approach

To reduce the copper oxides on the surfaces of oxidized‐copper for improving solder wettability with liquid lead‐free solder, this study attempted to apply Ar‐H2 plasmas to ablate the copper oxides from the surfaces of oxidized‐copper by the physical bombardment of the Ar plasmas and to reduce the surfaces of oxidized‐copper by the chemical reaction of H2 plasmas with the surfaces of oxidized‐copper.

Findings

The solder wettability of oxidized‐copper was found to be highly dependent on the surface characteristics of the copper. The values of polar surface free energy and dispersive surface free energy on the surfaces of oxidized‐copper modified by Ar‐H2 plasmas were close to those values of solid lead‐free solder, which resulted in improved solder wettability with liquid lead‐free solder. Auger spectra indicated that the Ar‐H2 plasma modification was used to remove the copper oxides from the surfaces of oxidized‐copper.

Originality/value

The surface characterization of copper surfaces is typically determined by expensive surface analysis tool such as Auger Electron Spectroscopy (AES). This paper reports the results of a study of a promising technique called the sessile drop test method, for examining the surface free energies such as total surface free energy, polar surface free energy and dispersive surface free energy on the surfaces of copper to clarify how the solder wettability of oxidized‐copper with liquid lead‐free solder was enhanced by Ar‐H2 plasmas.

Details

Soldering & Surface Mount Technology, vol. 24 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

1 – 10 of over 3000