Search results

The experience of using space apparatus type Shuttle testifies the unreliability of an applied design of a thermostable cover for flying apparatus made of separate tiles. To prevent burning through corps at branch and loss of separate heat-resistant termostable tiles when descending to earth from space, the technological idea of a continuous thermostable heat-resistant composite cover of flying apparatus for protection against dangerous effects of flame when landing on earth was introduced. The study also offers the idea of transformation of separate thermostable tiles in a continuous covering.

Development of the theory of natural structure of woven fabric for warp and weft threads in woven fabric upon release from external loadings in the woven machine on the basis of the principle of minimization of potential energy is presented. The method of calculation of the forces interaction between the warp and weft threads in the woven fabric structure is shown. Spontaneous change of the disposition of threads in the fabric structure after the removal of external loadings takes place by minimization of the total potential energy level of the deformed threads. The method of calculation of the key parameters of threads in the structure of a woven 2 dimensional fabric is achieved on the basis of the theory of mechanics. The work can be extended to cover industrial types of fabrics to reinforce textile composites.

This paper describes a new approach for the design of multilayer reinforcements of textile composite materials and products. We offer an alternative to multilayer complex fabrics for which the laminates of the composite reinforcement material consist of orthogonal woven fabrics with an original variable structure when each fabric layer is composed of alternating one‐ply (one warp and one weft) and one and‐ a‐half‐ply (one warp and two wefts) sections. Combination of these sections produces a “gearing” effect, preventing the delamination of textile composites in the process of their exploitation. An important aspect of the proposed method is a possibility to design woven fabrics in concurrence with the dimensions of the composite product and conditions of its exploitation; this leads to a substantial improvement of many properties of such composite product.

The purpose of this paper is to analyse the advantages of a new interpretation of the geometric disposition of threads within woven fabric structures, and to develop a method of determining the parameters of threads, with reference to each order of their disposition.

Based on the analysis of the geometrical models proposed by Barker and Midgely, by Pierce and by Novikov, the substantiation of the advantages of a stricter model, offered by the authors, for determining the geometric disposition of threads within single layer woven fabric structures with the help of the tangent function is given. This model allows the substantial expansion of the actual bounds of the interval of the order of the geometric disposition of threads in woven fabric structures to 0.2‐9.8.

The tangent function can approximate the crimp height ratio of the warp threads within the woven fabric structure with accuracy within the limits of geometric disposition angle change from 1° to 89°.

The work has applications in the industrial production of woven fabrics.

This research will allow the design of a woven fabric with practically any ratio of crimp height for the warp and weft threads to effectively achieve the required performance characteristics of the cloth.

This paper extends the knowledge of the geometrical characteristics of woven fabric structure, and proposes intelligent methods of determining the parameters of thread cross‐sections in accordance with the orders of the geometric disposition of threads in woven fabric structure.

In the work, the comparative analysis geometrical model of a transitional site of thread in structure of a woven fabric of a plain wave is resulted. Key parameters of an arrangement of threads in structure of a woven fabric are determined in view of crumple deformation up to the ellipse form of cross-section of a thread. The technology of their calculation is offered. The work could be expanded to industrial fabrics. Suggestion of the technology calculating of the ground parameters of threads disposition in structure of woven fabric are original and have a major contribution to textile science and technology.

The growing environmental awareness all through the world has motivated a standard change toward planning and designing better materials having good performance, which are very much suited to the environmental factors. The purpose of this study is to investigate the impact on mechanical, thermal and water absorption properties of sawdust-based composites reinforced by epoxy, and the amount of sawdust in each form.

Manufacturing of the sawdust reinforced epoxy composites is the main area of the research for promoting the green composite by having good mechanical properties, biodegradability or many applications. Throughout this research work, the authors emphasize the importance of explaining the methodology for the evaluation of the mechanical and water absorption properties of the sawdust reinforced epoxy composites used by researchers.

In this paper, a comprehensive review of the mechanical properties of sawdust reinforced epoxy composite is presented. This study is reported about the use of different Wt.% of sawdust composites prepared by different processes and their mechanical, thermal and water absorption properties. It is studied that after optimum filler percentage, mechanical, thermal properties gradually decrease, but water absorption property increases with Wt.% of sawdust. The changes in the microstructure are studied by using scanning electron microscopy.

The novelty of this study lies in its use of a systematic approach that offers a perspective on choosing suitable processing parameters for the fabrication of composite materials for persons from both industry and academia. A study of sawdust reinforced epoxy composites guides new researchers in the fabrication and characterization of the materials.

The purpose of the work is development a novel of hydro-vibration technology for the formation of hats from fabrics, which will expand the functionalities of application of various fabrics.

The work is based on a novel technology of forming hats from different fabrics with the use of liquid-active working environment (LAWE). This hydro-vibration technology is characterized by high efficiency, productivity, manufacturability and potential opportunities when compared to existing technologies. This allows expanding its range of applications and increase functionality.

In the article, hydro-vibration technology is developed for the formation of hats from fabrics. As a result of the experiment, regression dependences of the shape stability coefficient on the formation factors having a close correlation were obtained. The performed optimization allowed determining the optimal values of technological parameters of the vibroforming process from fabrics: LAWE pressure 0.26 MPa, vibration frequency LAWE 4.3 Hz, forming time 74 s.

The use of developed hydro-vibration technology has great practical significance in the textile industry. This technology increases labor productivity and reduces the cost of production of hats due to its high efficiency. Increased efficiency is provided by the use of special equipment, methods and optimal parameters of the hats formation. With sufficient refinement, the developed technology can be applied to other technological processes.

Originality of the work is using liquid-actin working environment at vibroforming of heads of headdresses from fabrics. It is determined that the use of LAWE is effective in the formation of hats. To ensure maximum plasticization of textile fibers in the fabric of the part and increase the force field, it is developed a novel hydro-vibration technology of forming the heads of hats from fabrics.

Internal hydrophobation by adding hydrophobic agents during the mixing process is a method for reducing water permeability of cement based materials. It can be used as an alternative to other methods such as reducing water cement ratio (w/c) or using silica fume (SF). However, it may affect other properties of cement based materials such as compressive strength. In this paper the results of an experimental study on compressive strength of different hcps with main variables w/c, SF and hydrophobic agents are presented. Rapeseed oil and alkyl alkoxysilane were selected as hydrophobic agents. Although, a low dosage of hydrophobic agents can be more effective than lowering w/c or adding SF in reducing water permeability, an obvious reduction was observed in compressive strength by this way of internal hydrophobation compared to the other above mentioned methods. Different reasons such as lower hydration degree, chemical reactions of hydrophobic agents and non-uniform distribution of hydrophobic materials in the hcp could have resulted in lower compressive strength of hydrophobed samples. Using other types of hydrophobic agents or impregnation after the curing process can be other alternatives which would have less effect on compressive strength.