scholarly journals Microstructural analysis of non-woven fabrics using scanning electron microscopy and image processing. Part 2: Application to hydroentangled fabrics

2002 ◽  
Vol 216 (4) ◽  
pp. 211-218 ◽  
Author(s):  
E Ghassemieh ◽  
M Acar ◽  
H K Versteeg
Keyword(s):  
Fibre Orientation ◽  
Microstructural Analysis ◽  
Length Distribution ◽  
Fibre Length ◽  
Orientation Distribution ◽  
Woven Fabrics ◽  
Analysis Techniques ◽  
Image Analysis Techniques ◽  
Degree Of Entanglement ◽  
Fibre Orientation Distribution

The image analysis techniques developed in Part 1 to study microstructural changes in non-woven fabrics are applied to measure the fibre orientation distribution and fibre length distribution of hydroentangled fabrics. The results are supported by strength and modulus measurements using samples from the same fabrics. It is shown that the techniques developed can successfully be used to assess the degree of entanglement of hydroentangled fabrics regardless of their thickness.

scholarly journals DECIPHERING THE FINEST IMPRINT OF GLACIAL EROSION: OBJECTIVE ANALYSIS OF STRIAE PATTERNS ON BEDROCK

2011 ◽  
Vol 23 (3) ◽  
pp. 135 ◽  
Author(s):  
Piet Stroeven ◽  
Arjen Peter Stroeven ◽  
Jing Hu ◽  
Jean-Louis Chermant ◽  
Michel Coster
Keyword(s):  
Experimental Data ◽  
Image Analysis ◽  
Fourier Transform ◽  
Fast Fourier Transform ◽  
Orientation Distribution ◽  
Experimental Investigations ◽  
Automatic Image Analysis ◽  
Glacial Erosion ◽  
Analysis Techniques ◽  
Image Analysis Techniques

The aim of this study is to compare the efficiency of different mathematical and statistical geometrical methods applied to characterise the orientation distribution of striae on bedrock for deciphering the finest imprint of glacial erosion. The involved methods include automatic image analysis techniques of Fast Fourier Transform (FFT), and the experimental investigations by means of Saltikov's directed secants analysis (rose of intersection densities), applied to digital and analogue images of the striae pattern, respectively. In addition, the experimental data were compared with the modelling results made on the basis of Underwood's concept of linear systems in a plane. The experimental and modelling approaches in the framework of stereology yield consistent results. These results reveal that stereological methods allow a reliable and efficient delineation of different families of glacial striae from a complex record imprinted in bedrock.

scholarly journals Modelling the permeability of random discontinuous carbon fibre preforms

2020 ◽  
Vol 54 (20) ◽  
pp. 2739-2751
Author(s):  
Zhaofei Xiao ◽  
Xiaoling Liu ◽  
Lee T Harper ◽  
Andreas Endruweit ◽  
Nicholas A Warrior
Keyword(s):  
Carbon Fibre ◽  
Volume Fraction ◽  
Fibre Orientation ◽  
Orientation Distribution ◽  
Binder Content ◽  
Fibre Bundles ◽  
Local Permeability ◽  
Meso Scale ◽  
Fibre Orientation Distribution ◽  
Upper Boundary

A force-directed algorithm was developed to create representative geometrical models of fibre distributions in directed carbon fibre preforms. Local permeability values were calculated for the preform models depending on the local fibre orientation, distribution and volume fraction. The effect of binder content was incorporated by adjusting the principal permeability values of the meso-scale discontinuous fibre bundles, using corresponding experimental data obtained for unidirectional non-crimp fabrics. The model provides an upper boundary for the permeability of directed carbon fibre preform architectures, where predictions are within one standard deviation of the experimental mean for all architectures studied.

Modeling Bending Rigidity of Nonwovens with 2D Structures

2010 ◽  
Vol 156-157 ◽  
pp. 387-391
Author(s):  
Hua Wu Liu ◽  
Zhi Gang Chen ◽  
Ping Xu
Keyword(s):  
Theoretical Model ◽  
Fibre Orientation ◽  
Orientation Distribution ◽  
Single Fibre ◽  
Original Position ◽  
Dimensional Structure ◽  
Two Dimensional ◽  
Bending Rigidity ◽  
Bending Behaviour ◽  
Fibre Orientation Distribution

A theoretical model was developed to describe the bending behaviour and property of nonwovens with two-dimensional structure. The bending and tensional behaviours of single fibre with and without slippage in a bent fabric were analyzed. The method determining the neutral plane of bent nonwovens and the bending rigidity of fabrics with general two-dimensional structure were developed, incorporating fibre orientation distribution, number of fibres, fibre original position before bending and the Poisson’s ratio of the fabric. The analyses also give the fibre orientations that lead to the maximum and minimum contributions to the bending rigidity of the nonwovens in laminate and sandwich structures

Fibre orientation measurements near a headbox wall

2010 ◽  
Vol 25 (2) ◽  
pp. 204-212 ◽  
Author(s):  
Allan Carlsson ◽  
L. Daniel Söderberg ◽  
Fredrik Lundell
Keyword(s):  
Fibre Orientation ◽  
Orientation Distribution ◽  
Laboratory Scale ◽  
Experimental Results ◽  
Dilute Suspensions ◽  
Steerable Filter ◽  
Fibre Orientation Distribution

Abstract Experimental results on the fibre orientation in a laboratory scale headbox are reported. Images containing fibres in approximately 1 mm thick slices parallel to the wall were captured at different wall distances. A steerable filter was used to determine the orientation of bleached and unbeaten birch fibres, suspended in water, at different distances from one of the inclined walls of the headbox contraction. Due to optical limitations only dilute suspensions were studied. It is shown that the fibre orientation distribution varies with the distance from the wall. Sufficiently far upstream in the headbox a more anisotropic distribution is found closer to the wall.

Determination of fibre orientation distribution in reinforced sands

Géotechnique ◽  
2007 ◽  
Vol 57 (7) ◽  
pp. 623-628 ◽  
Author(s):  
A. Diambra ◽  
A. R. Russell ◽  
E. Ibraim ◽  
D. Muir Wood
Keyword(s):  
Fibre Orientation ◽  
Orientation Distribution ◽  
Fibre Orientation Distribution

Fibre Orientation and Mechanical Properties of Short Glass Fibre Reinforced PP Composites

2005 ◽  
Vol 13 (3) ◽  
pp. 253-262 ◽  
Author(s):  
Minjie Chen ◽  
Chaoying Wan ◽  
Yong Zhang ◽  
Yinxi Zhang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Glass Fibre ◽  
Fibre Orientation ◽  
Orientation Distribution ◽  
Efficiency Factor ◽  
Short Glass Fibre ◽  
Pp Composites ◽  
Short Glass ◽  
Fibre Orientation Distribution

The fibre orientation and distribution in short glass fibre (SGF) reinforced polypropylene (PP) composites were measured and an orientation function ( f) was introduced to describe the fibre orientation distribution. The fibre orientation distribution in the same level plane depended on the fibre position in an injection-moulded plate. The fibres close to the boundary wall of the injection cavity were parallel to the injection direction and those close to the back wall were perpendicular to the injection direction. A commercial maleic anhydride grafted PP (MAPP) was used as a compatibilizer. With the addition of MAPP, the fibre orientation distribution in PP/SGF/MAPP composites was slightly different from that of PP/SGF, but MAPP improved the interfacial adhesion between SGF and PP and consequently the mechanical properties. The use of SGF increased the tensile strength of the PP composites from 26.5 to 45.9 MPa (73% improvement), and for the PP/MAPP/SGF composite the tensile strength increased further to 55.4 MPa. The effect of SGF on the tensile strength can be expressed by a fibre efficiency factor (λσ). The SGF efficiency factor of PP/MAPP/SGF (0.198) was 45% higher than that of PP/SGF (0.137). The impact strength of PP/MAPP/SGF (64.7 MPa) was not only higher than that of PP/SGF (40.8 MPa) by 59% but also higher than that of PP (48.3 MPa) by 34%.

Sign in / Sign up

Export Citation Format

Share Document