Critical Review of Natural Fiber Reinforced Hybrid Composites: Processing, Properties, Applications and Cost

Increasing scientific interest has occurred concerning the utilization of natural fiber-enhanced hybrid composites that incorporate one or more types of natural enhancement. Annual natural fiber production is estimated to be 1,783,965 × 103 tons/year. Extensive studies have been conducted in the domains of natural/synthetic as well as natural/natural hybrid composites. As synthetic fibers have better rigidity and strength than natural fibers, natural/synthetic hybrid composites have superior qualities via hybridization compared to natural composites in fibers. In general, natural fiber compounds have lower characteristics, limiting the use of natural composites reinforced by fiber. Significant effort was spent in enhancing the mechanical characteristics of this group of materials to increase their strengths and applications, especially via the hybridization process, by manipulating the characteristics of fiber-reinforced composite materials. Current studies concentrate on enhancing the understanding of natural fiber-matrix adhesion, enhancing processing methods, and natural fiber compatibility. The optimal and resilient conceptions have also been addressed due to the inherently more significant variabilities. Moreover, much research has tackled natural fiber reinforced hybrid composite costs. In addition, this review article aims to offer a review of the variables that lead to the mechanical and structural failure of natural fiber reinforced polymer composites, as well as an overview of the details and costings of the composites.

REPRESENTATION, CHARACTERIZATION AND SIMULATION OF TOOL-PART INTERACTION AND ITS EFFECTS ON PROCESS-INDUCED DEFORMATIONS IN COMPOSITES

The interaction between a tool and part during composites processing contributes to the formation of residual stresses and dimensional changes. A resultant mismatch of part geometries during assembly can cause a potential loss of mechanical performance in aerospace structures. Costly shimming steps are needed to compensate for processinduced deformations and satisfy specifications on mechanical performance. Due to difficulties associated with accurate measurement of interfacial shear stresses, current analysis methods fail to represent the interaction between a tool and part throughout processing. A combined approach to represent, characterize, and simulate tool-part interaction and its effects on dimensional changes is proposed. First, a characterization method was established using a custom Dynamic Mechanical Analysis (DMA) shear test setup to measure tool-part interfacial stress development in a simulated autoclave curing environment. Tool-part interfacial stresses were characterized for Toray T800S/3900-2 UD prepreg as a function of temperature, degree of cure, strain rate, and tool surface condition. Then, a previously developed numerical model was modified to include the effects of tool-part interaction in predicting dimensional changes of L-shape parts. For validation, composite parts were fabricated on tools with different surface conditions and successfully compared to simulation results. This paper demonstrates that tool-part interaction significantly impacts the spring-in of angled composite parts. The proposed method is a comprehensive and practical approach to study and simulate the effects of tool-part interaction. The results of this paper can be used to understand the complex interaction between a tool and part throughout processing and potentially mitigate processinduced deformations.

Natural Fiber-based Green Composites: Processing, Properties and Biomedical Applications

Since the advent of modern technological civilization, tremendous pollution has been done in our environment by disposing of waste material in the environment unconsciously. Some waste materials are biodegradable and some of them are non-biodegradable. Biodegradable waste, originated from plants or animals can be decomposed by the natural organism (bacteria, fungi, etc.) and not be adding to pollution. This degradation process may be rapid or slow but the environmental risks are low. On the other hand, non-biodegradable waste, obtained from inorganic components cannot be decomposed by the natural organism and acts as a source of pollution. These wastes are being generated by humans and every year billions of tons of wastes are being dumped into the environment which puts our environment in danger. Even if it is late, mankind has realized that unless the nature is out of danger, he himself will be endangered. As a result, environmental consciousness has increased worldwide. This growing ecological and environmental awareness leads the world to develop eco-friendly materials. As the population grows day by day, it is not possible to reduce waste. So, it is wise to focus on developing new materials that would produce biodegradable waste. Recently the attraction on the biocomposite (known as green composites) materials has significantly increased because it is generated from natural fiber which is biodegradable and it has the potential of being a substitute for conventional non-biodegradable products. Biocomposites are used in various industrial sectors, including the bio-medical industry. In this paper, the overall idea of natural fibers, extraction and surface modification methods of natural fiber, Natural fiber-based biocomposites, fabrication and properties analysis of biocomposite,and recent applications of biocomposites in the bio-medical sector have been reviewed. The primary incentive for developing and using biocomposite is to build a new generation of eco-friendly materials by replacing synthetic ones.

Educational and scientifi c "Center for Additive Polymer Technologies" - cooperation of the Department of HCCI and PC with TOTALZED LLC (TOTAL-Z)

The issues of molding products from polymer materials and composites using additive technologies (ADT), which are one of the modern trends in the technology of processing polymer materials and composites into products with complex geometry of various standard sizes, are considered. It is shown that the creation of ADT is a complex scientifi c and technical task. The data on TOTAL-Z LLC, the Russian manufacturer of 3D-printers, and model range of printers are presented. The role of RTU MIREA’s Department of Chemistry and Technology of Plastics and Polymer Composites Processing, together with TOTAL-Z LLC, in the organization of the first educational and scientific center for additive polymer technologies, training and development of additive technologies is shown.