Development Of High-performance Fibers Research Articles

Interfibrillar behavior in ultra-high molecular weight polyethylene (UHMWPE) single fibers subjected to tension

In this effort, the interfibrillar behavior in UHMWPE fibers subjected to tension is investigated using a unique experimental setup that allows for the in-situ monitoring of the deformations of sub-fiber level components within the fiber. Digital image correlation (DIC) is used to measure fiber surface strains, quantify the stress-strain fiber response and interfibrillar sliding between adjacent macrofibrils within the fiber’s microstructure, and estimate the length of macrofibrils within the fiber. Finite element (FE) based models of the UHMWPE fibers are developed that account for the complex fibrillar microstructure and macrofibrillar interactions governing the macro-scale fiber response under uniaxial tension. The FE-based models are compared to both experimental results and previously developed analytical fiber models to study the effects of underlying model assumptions on the fiber’s stiffness and deformation response. The shortcomings of a continuum material model for the fiber are revealed. A unique beam connector model of the fiber is presented which mimics the inherent interfibrillar deformation mechanics observed in the experiments. A Design of Experiments (DoE) approach is used to facilitate development of the model. Predictions are shown to compare favorably with experimental results for both the fiber stress-strain response and the degree of interfibrillar sliding. The findings presented in this paper contribute towards the fundamental understanding of the complex microstructure-property relations in UHMWPE fibers and can ultimately be used to help guide the development of high performance fibers widely used in armor ballistic protection systems.

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

溶融延伸による高性能繊維・膜の創製

溶融延伸による高性能繊維・膜の創製

繊維強化複合材料の高性能化と新たな構造・物性解析法の提案

繊維強化複合材料の高性能化と新たな構造・物性解析法の提案

Fuzzy Rule based Modeling of Drilling Parameters for Tool Wear in Drilling GFRP Composites

The most recent development of high performance fibers has led to the availability of composites which can compete and indeed replace metals. Just like any other engineering material GFRP’s have to be machined as well. Amongst the three machining operations of turning, milling and drilling, the latter is the most important. Drilling of GFRP is different from traditional metal machining because of the following concerns. In machining of GFRP the drill bit experiences variable thrust forces that produces excess vibration results in poor tool life. Apart from force fluctuations, cutting tools also experience severe abrasion on the flank surface, due to encounter with hard glass fiber. In this work, experiments were conducted in CNC milling machine for carbide drill bit based on L9 orthogonal array. The process parameters investigated are spindle speed, feed rate, and drill diameter. Fuzzy rule based model is developed to predict the thrust force in drilling GFRP. The results indicated that the model can be effectively used for predicting the response variable by means of which tool wear can be controlled.

Development of high performance fiber reinforced cement composites (HPFRCC) for application as a transition layer of reinforced beams

This study presents the development and behavior analysis of high performance fiber reinforced cement composites (HPFRCC). The describedmaterials were specifically developed for application as a transition layer: a repair layer that constitutes the stressed chord of reinforcedconcrete beams strengthened in flexure with carbon fiber reinforced polymers (CFRP). Nineteen different composites were produced by thehybridization process, varying the conventional short steel fiber and steel microfiber (manufactured exclusively for this research) contentsto modify the microstructure of the material, thus enhancing the stress transfer process from the cement matrix to the fibers. To analyze theresponse to flexural loading, the composites underwent three point bending tests in notched prism specimens. The response of the materialwas obtained considering strength and tenacity parameters (flexural and fracture). There was evidence of high performance by the composites with a pseudo-hardening behavior.

Selective Use of High Performance Cementitious Composites in Concrete Structures

Recent advancements in concrete science and technology have made possible the development of high performance fiber reinforced cementitious composites (HPFRCC) with excellent mechanical properties and long-term durability. However, the costs of these materials are many times that of conventional concrete and the construction of complete structures with them is hard to justify. The strategic application of high performance materials, in selected parts of concrete structures, can bring along higher performance/cost and wider acceptance of the material in practice. This paper will investigate several examples of selective HPFRCC application, including the fabrication of permanent formwork for durability enhancement, the replacement of steel reinforcements at the anchorage zone of post-tensioned members to relieve the steel congestion problem as well as the development of simple and narrow joints for pre-cast concrete members. Based on the experimental results obtained so far, the selected use of HPFRCC in concrete structures appears to have good potential for practical applications.

Development of High Performance Fiber Reinforced Composite with Negative Thermal Expansion Property

There are exists positive thermal expansion property for almost all materials. However, in many cases, the material property with negative thermal expansion is requested for engineering applications. This work is to develop high performance fiber-reinforced composites with negative thermal expansion by using high strength polyethylene fiber Dyneema®, high strength PBO fiber ZYLON®, aramid fiber Technora ® and carbon fibers.

Development of High Performance Fiber Reinforced Cementitious Composites

Development of High Performance Fiber Reinforced Cementitious Composites

Deformation Micromechanics of a Thermoplastic—Thermoset Fiber—Matrix Interface using the Single Fiber Composite Test

The development of high performance fibers, based on polyethylene (PE) fiber opened the possibility of manufacturing composites with high strength and lightness and gave a modern application to an old fashioned material. In the present study, the interfacial micromechanics between gel-spun PE fibers and epoxy resin is studied using Raman spectroscopy. The poor adhesive properties between PE and any matrix material makes it ideal for studying the debonding process; the interfacial failure is relatively easy to promote. The study of the deformation micromechanics and failure of the thermoplastic—thermoset interface will eventually lead to the control of this type of hybrid composite, which represent a new kind of materials. The single fiber composite geometry was used to study the interface and how it was affected by different chemical treatments on the fiber surface, which created an interface between the PE fiber and the epoxy matrix. Prior to treatment, the interaction between them was nonexistent. Stress profiles along the fiber were obtained using Raman spectroscopy and the interface performance was assessed using a partial debonding model. The results not only lead to calculation of the interfacial shear stress (ISS), but also aid in understanding the debonding process and levels of stress required for the composite interface to fail.