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1

Response Surface Modeling of Physical and Mechanical Properties of Cotton Slub Yarns

Qadir M. B., Malik Z. A., Ali U., Shahzad A., Hussain T., Abbas A., Asad M., Khaliq Z.

Autex Research Journal

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2018

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Vol. 18, no. 2

173--180

EN

The objective of this study was to model the physical and mechanical properties of 100% cotton slub yarns commonly used in denim and other casual wear. Statistical models were developed using central composite experimental design of the response surface methodology. Yarn’s linear density, slub thickness, slub length and pause length were used as the key input variables while yarn strength, elongation, coefficient of mass variation, imperfections and hairiness were used as response/output variables. It was concluded that yarn strength and elongation increased with increase in linear density and pause length, and decreased with increase in slub thickness and slub length. Yarn mass variation and total imperfections increased with increase in slub thickness and pause length, whereas yarn imperfections and hairiness decreased with increase in slub length. It was further concluded that due to statistically significant square and interaction effects of some of the input variables, only the quadratic model instead of the linear models can adequately represent the relationship between the input and the output variables. These statistical models will be of great importance for the industrial personnel to improve their productivity and reduce sampling.

2

Use of Taguchi Method and Grey Relational Analysis to Optimize Multiple Yarn Characteristics in Open-End Rotor Spinning

Hussain T., Arain F., Malik Z. A.

Autex Research Journal

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2017

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Vol. 17, no. 1

67--72

EN

Rotor speed and twist per metres (tpm) are two key parameters in open-end rotor spinning of cotton yarns. High spinning productivity can be obtained by keeping the rotor speed high and twist level as low as possible. However, too high rotor speed may result in yarn imperfections and too low twist level may result in lower tenacity yarns. This study aimed at optimising the multiple yarn characteristics in open-end rotor spinning using the Taguchi method and the grey relational analysis. Cotton yarn samples of 30 tex were produced on rotor spinning machine with different twist levels (i.e. 500, 550, 600 and 700 tpm) at different rotor speeds (i.e. 70,000, 80,000, 90,000 and 100,000 rpm) according to the Taguchi design of experiment. Optimal spinning process parameters were determined using the grey relational grade as the performance index. It was concluded that for the cotton fibres and yarn count used in this study, optimum properties of the yarns could be obtained at 90,000 rpm rotor speed and 700 tpm.

3

Prediction and Correlation of Air Permeability and Light Transmission Properties of Woven Cotton Fabrics

Nazir A., Hussain T., Afzal A., Faheem S., Ibrahim W., Bilal M.

Autex Research Journal

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2017

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Vol. 17, no. 1

61--66

EN

The aim of this study was to develop statistical models for predicting the air permeability and light transmission properties of woven cotton fabrics and determine the level of correlation between the two parameters. Plain woven fabrics were developed with different warp and weft linear densities, ends per inch and picks per inch. After desizing, scouring, bleaching, drying and conditioning, the air permeability and light transmission properties of the fabric samples were determined. Regression analysis results showed statistically significant effect of the fabric ends, picks and warp linear density on both the fabric air permeability and light transmission. Correlation analysis was performed to analyze the relation between the fabric air permeability and light transmission. A linear equation was also formulated to find the fabric air permeability through transmission of light intensity. A fitted line plot between the air permeability and light transmission exhibited significant correlation with R-sq. value of 96.4%. The statistical models for the prediction of fabric air permeability and light transmittance were developed with an average prediction error of less than 7%.

4

Desensitization by Pre-shocking in Heterogeneous Explosives and its Numerical Modelling

Hussain T., Yan L., Fenglei H., Yi L.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 2

357--379

EN

Desensitization caused by pre-shocking in heterogeneous explosives is discussed. The aim of this study was to find a simple numerical model that could reproduce the important features of previously reported shock desensitization experiments. After reviewing the previous experimental results and modelling efforts, an extension of the Lee-Tarver reactive flow model is proposed. The proposed desensitization model is based upon the experimentally determined desensitization criteria for explosives. The additional parameters required for this extension can be calibrated by experiment for a typical explosive. The new model has been implemented in the hydrodynamic code LS-DYNA as a user defined equation of state, and is now available to simulate various kinds of situations involving explosives up to the limits and capabilities of LS-DYNA. Desensitization by pre-shocking in double shock experiments, reflected shock and detonation quenching experiments have been studied using the new model, and the results were found to be in qualitative agreement with the experimental results reported in the literature.

5

Improving Thermo-Physiological Comfort of Polyester/Cotton Knits by Caustic and Cellulases Treatments

Nazir A., Hussain T., Zia Q., Afzal M. A.

Autex Research Journal

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2014

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Vol. 14, no. 3

200--204

EN

Cotton is one of the most commonly used fibres for making knitwear. Some of the limitations of pure cotton knits include their tendency to shrink, relatively limited durability, and poor wash and wear properties. In order to overcome these limitations knitwear are also produced from polyester and cotton blends, however, at the cost of reduction in comfort properties. The objective of this study was to improve the thermo-physiological comfort properties of knits made from polyester/cotton (P/C) blends through simple chemical and biological treatments. The specimens of P/C knits were subjected to treatments with caustic soda solutions and the cellulase enzymes. It was found that the air permeability and perspiration management properties of P/C knits can be significantly improved by appropriate caustic treatment. However, the biological treatment with cellulase enzymes is comparatively less effective in making any improvement in the thermo-physiological comfort properties of P/C knits.

6

Effect of knitting parameters on moisture management and air permeability of interlock fabrics

Nazir A., Hussain T., Ahmad F., Faheem S.

Autex Research Journal

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2014

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Vol. 14, no. 1

39--46

EN

The aim of this study was to investigate the effect of knitting parameters on the moisture management and air permeability of the interlock fabrics. Samples were produced at two different knitting gauges, each with three different stitch lengths. It was found that the fabric mass per square metre increases by increasing machine gauge and decreasing the stitch length, whereas the fabric thickness and porosity increase at these settings. It was further concluded that the loosely knitted fabric samples with higher amount of entrapped air exhibit good air permeability but poor moisture management properties.

7

Existence of zero-group velocity modes in an incompressible plate

Hussain T., Ahmad F.

Archives of Mechanics

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2014

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Vol. 66, nr 1

55--65

EN

Zero-group velocity (ZGV) Lamb modes are studied in an incompressible orthotropic plate. The existence of such modes critically depends on the anisotropy parameter a = (c11 + c22 − 2c12 − 4c66)/c66. With materials having a > −1, none of the modes possesses any ZGV points and every mode has such a point if a < −1. Several modes have multiple ZGV points.

8

Effect of sewing parameters and wash type on the dimensional stability of knitted garments

Malik M. H., Malik Z. A., Hussain T., Ramzan M. B.

Autex Research Journal

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2013

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Vol. 13, no. 3

89--94

EN

The aim of this research is to study the effect of clothing manufacturing parameters, that is, stitch type, stitch density, sewing thread type and washing type on the dimensional stability of single jersey knitted garment. Single jersey bleached fabric, made from Ne 32 cotton combed ring spun yarn, was used to make 32 medium size crew neck T-shirts selecting two levels of stitch type, stitch density, sewing thread type and wash type according to the experimental design. After constructing the garments, four critical measurements of each garment, that is, body length, body width, across shoulder and sleeve length were measured. The constructed garments were divided into two equal groups. One group was washed with water and the other group was washed using a detergent. After washing, drying and tumbling, the same critical measurements of each garment were taken and the percent shrinkage was calculated. Analysis of data was done on responses of output variables against the input variables using MINITAB. The results showed that three input variables: stitch type, stitch density and garment wash type have significant effect on all the output variables.