This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabric...This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabrics in terms of the low - stress mechanical properties of bending, shear, and tensile deformation. It is found that there are very significant correlations between the corresponding parameters for extensibility and shear rigidity obtained from the test results of the two systems. The correlation between the values of bending rigidity obtained from the two systems is only moderate. Furthermore, for the fabrics tested in this study, the values of bending rigidity, shear rigidity, and extensibility measured using the KES - F instruments are higher than those of the corresponding parameters measured using the FAST instruments. The linear regression equation is given for each pair of corresponding parameter.展开更多
The differences of rock mechanical properties were analyzed based on triaxial compression test in low permeability reservoirs of the Bonan Oilfield. Through the analysis of reservoir mechanics, the influence mechanism...The differences of rock mechanical properties were analyzed based on triaxial compression test in low permeability reservoirs of the Bonan Oilfield. Through the analysis of reservoir mechanics, the influence mechanisms of different mechanical properties of rocks on reservoir in-situ stress were studied. By means of stress ellipse and finite element simulation, the influence rules of different mechanical properties of rocks on in-situ stress field were discussed. For the low permeability reservoirs of the Bonan Oilfield, the coarser rock has a larger Young’s modulus value and a lower Poisson’s ratio. The rock mechanical parameters and stress-strain relationship of sandstone facies and mudstone facies are different. Different rocks have different mechanical properties, which cause extra stress at the lithological contact interface, and the existence of extra stress affects the reservoir in-situ stress. Without considering the influence of structural features on the in-situ stress field, the reservoir in-situ stress is controlled by the magnitude of extra stress and the angle between lithological contact surface and boundary stress.展开更多
The wool fabrics were treated with low temperature plasma (LTP) using three different gases, namely (ⅰ) oxygen, (ⅱ) nitrogen and (ⅲ) 25％ hydrogen/75％ nitrogen gas mixture. After LTP treatment, the low stress mech...The wool fabrics were treated with low temperature plasma (LTP) using three different gases, namely (ⅰ) oxygen, (ⅱ) nitrogen and (ⅲ) 25％ hydrogen/75％ nitrogen gas mixture. After LTP treatment, the low stress mechanical properties, surface properties and thermal properties of the fabrics were investigated by kES-F (Kawabata Evaluation System) Instruments composing of KES-FBI for tensile and shear property measurement, KES-FB2 for pure bending measurement, kES-FB3 for compression measurement, KES-FB4 for surface friction and surface roughness measurement, and KES-F7 for thermal property measurement. The first four instruments were used for investigating the charaeterlstlc aspect related to fabrle hand while the last one was mainly for the fabric comfort. The properties of LTP treated fabrics under the effect of different gases were compared with the untreated fabric quantitatively.展开更多
A theoretical model with extensible yarns for plain-woven fabrics is developed to determine the calculation of Poisson ratios.The stress ratio( warp: weft),as one of parameters corresponding to Poisson ratio variation...A theoretical model with extensible yarns for plain-woven fabrics is developed to determine the calculation of Poisson ratios.The stress ratio( warp: weft),as one of parameters corresponding to Poisson ratio variations, is introduced to complement the theoretical model. To evaluate the reliability of the theoretical analysis,a series of biaxial tensile tests of a plain-woven fabric with nine stress ratios are conducted carefully,and the theoretical results are compared with the experimentally measured values. The effects of other influencing factors, including geometric and mechanical parameters of yarns,on Poisson ratios are analyzed thoroughly.This solution method could be applied without difficulty to estimations of Poisson ratios and realistic designs for plain-woven fabrics.展开更多
To fulfill the sustainability need of today’s comfort conscious consumers, an attempt has been made in this research study to explore the possibilities of producing high-quality apparel fabrics using unconventional f...To fulfill the sustainability need of today’s comfort conscious consumers, an attempt has been made in this research study to explore the possibilities of producing high-quality apparel fabrics using unconventional fiber fabrics and their union fabrics. Unconventional natural fibers such as banana, hemp, linen and ramie and also their union fabrics with cotton were used. Union fabrics have different fiber content in warp and weft directions. A comparative study was made on the comfort behavior of these fabrics to evaluate their comfort performance. The properties of these fabrics were evaluated and compared under air permeability, moisture management, thermal properties, low-stress mechanical properties, etc. Unconventional fiber fabrics showed better results in many cases and thus were comparable with 100% cotton fabrics.展开更多
Low carbon steel wires were prepared by two processes,serial drawing(SD)and reverse-direction drawing(RD).Effects of the two processes on microstructure and mechanical properties in steel wires were investigated by fi...Low carbon steel wires were prepared by two processes,serial drawing(SD)and reverse-direction drawing(RD).Effects of the two processes on microstructure and mechanical properties in steel wires were investigated by field emissio scanning electron microscopy,electron backscatter diffraction(EBSD),X-ray diffraction and transmission electron microscopy(TEM).Residual compressive stress and more low-angle grain boundaries were introduced into the steel wire by the RD.As a result,the RD wires exhibited a greater tensile strength when drawing strain s<1.18.The SD encouraged grain refinement and texture formation in the wire.The SD wires exhibited a smaller average width of the elongated ferrite grain and a higher intensity of(110)fiber texture at all drawing strains.Therefore,the SD wires showed a bit greater tensile strength and 20%greater torsion performance than the RD wires at c=2.51.TEM and EBSD analysis indicated that dislocation tangle was formed easily in RD wires,and it transformed into twist boundary.This twist boundary impeded the grain refinement in the RD wires,and there were still non-fibrous grains in the RD wires even after heavy drawing.展开更多
基金This project was generously funded by International Wool Secretariat
文摘This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabrics in terms of the low - stress mechanical properties of bending, shear, and tensile deformation. It is found that there are very significant correlations between the corresponding parameters for extensibility and shear rigidity obtained from the test results of the two systems. The correlation between the values of bending rigidity obtained from the two systems is only moderate. Furthermore, for the fabrics tested in this study, the values of bending rigidity, shear rigidity, and extensibility measured using the KES - F instruments are higher than those of the corresponding parameters measured using the FAST instruments. The linear regression equation is given for each pair of corresponding parameter.
基金Supported by the China National Major Demonstration Project(2017ZX05072)
文摘The differences of rock mechanical properties were analyzed based on triaxial compression test in low permeability reservoirs of the Bonan Oilfield. Through the analysis of reservoir mechanics, the influence mechanisms of different mechanical properties of rocks on reservoir in-situ stress were studied. By means of stress ellipse and finite element simulation, the influence rules of different mechanical properties of rocks on in-situ stress field were discussed. For the low permeability reservoirs of the Bonan Oilfield, the coarser rock has a larger Young’s modulus value and a lower Poisson’s ratio. The rock mechanical parameters and stress-strain relationship of sandstone facies and mudstone facies are different. Different rocks have different mechanical properties, which cause extra stress at the lithological contact interface, and the existence of extra stress affects the reservoir in-situ stress. Without considering the influence of structural features on the in-situ stress field, the reservoir in-situ stress is controlled by the magnitude of extra stress and the angle between lithological contact surface and boundary stress.
文摘The wool fabrics were treated with low temperature plasma (LTP) using three different gases, namely (ⅰ) oxygen, (ⅱ) nitrogen and (ⅲ) 25％ hydrogen/75％ nitrogen gas mixture. After LTP treatment, the low stress mechanical properties, surface properties and thermal properties of the fabrics were investigated by kES-F (Kawabata Evaluation System) Instruments composing of KES-FBI for tensile and shear property measurement, KES-FB2 for pure bending measurement, kES-FB3 for compression measurement, KES-FB4 for surface friction and surface roughness measurement, and KES-F7 for thermal property measurement. The first four instruments were used for investigating the charaeterlstlc aspect related to fabrle hand while the last one was mainly for the fabric comfort. The properties of LTP treated fabrics under the effect of different gases were compared with the untreated fabric quantitatively.
基金National Natural Science Foundations of China(Nos.51278299)Natural Science Foundation of the Jiangsu Province,China(No.BK 20150775)
文摘A theoretical model with extensible yarns for plain-woven fabrics is developed to determine the calculation of Poisson ratios.The stress ratio( warp: weft),as one of parameters corresponding to Poisson ratio variations, is introduced to complement the theoretical model. To evaluate the reliability of the theoretical analysis,a series of biaxial tensile tests of a plain-woven fabric with nine stress ratios are conducted carefully,and the theoretical results are compared with the experimentally measured values. The effects of other influencing factors, including geometric and mechanical parameters of yarns,on Poisson ratios are analyzed thoroughly.This solution method could be applied without difficulty to estimations of Poisson ratios and realistic designs for plain-woven fabrics.
文摘To fulfill the sustainability need of today’s comfort conscious consumers, an attempt has been made in this research study to explore the possibilities of producing high-quality apparel fabrics using unconventional fiber fabrics and their union fabrics. Unconventional natural fibers such as banana, hemp, linen and ramie and also their union fabrics with cotton were used. Union fabrics have different fiber content in warp and weft directions. A comparative study was made on the comfort behavior of these fabrics to evaluate their comfort performance. The properties of these fabrics were evaluated and compared under air permeability, moisture management, thermal properties, low-stress mechanical properties, etc. Unconventional fiber fabrics showed better results in many cases and thus were comparable with 100% cotton fabrics.
基金This work is supported by the National Natural Science Foundation of China(Grant No.51371050)Special Talent Program of Jiangsu Province(2015-XCL-004)+2 种基金the Industry・University Strategic Research Fund of Jiangsu Province(BY2016076-08)The study is also partly supported by the Science and Technology Advancement Program of Jiangsu Province(Grant No.BA2017112)L.C.Zhou appreciates the support provided by Fundamental Research Funds for the Central Universities and the Scientific Research Foundation of the Graduate School of Southeast University(YBJJ1674).
文摘Low carbon steel wires were prepared by two processes,serial drawing(SD)and reverse-direction drawing(RD).Effects of the two processes on microstructure and mechanical properties in steel wires were investigated by field emissio scanning electron microscopy,electron backscatter diffraction(EBSD),X-ray diffraction and transmission electron microscopy(TEM).Residual compressive stress and more low-angle grain boundaries were introduced into the steel wire by the RD.As a result,the RD wires exhibited a greater tensile strength when drawing strain s<1.18.The SD encouraged grain refinement and texture formation in the wire.The SD wires exhibited a smaller average width of the elongated ferrite grain and a higher intensity of(110)fiber texture at all drawing strains.Therefore,the SD wires showed a bit greater tensile strength and 20%greater torsion performance than the RD wires at c=2.51.TEM and EBSD analysis indicated that dislocation tangle was formed easily in RD wires,and it transformed into twist boundary.This twist boundary impeded the grain refinement in the RD wires,and there were still non-fibrous grains in the RD wires even after heavy drawing.
