Reviewing the Development of Natural Fiber Polymer Composite: A Case Study of Sisal and Jute
Gbenga Ekundayo,
Sam Adejuyigbe
Issue:
Volume 3, Issue 1, March 2019
Pages:
1-10
Received:
7 December 2018
Accepted:
11 January 2019
Published:
22 February 2019
Abstract: Natural fibers that are mainly from plants, animals and regenerated sources are degradable and environmentally friendly as they absorb carbon dioxide and release oxygen, they are cost effective when compare to the synthetic fibers. These materials mainly from plant are used initially for domestics’ purposes. They have recently been introduced to some industries, such as automotive, aircraft, marine and buildings, arising from their excellent mechanical, physical and chemical properties. The common natural fibers used for Natural Fiber Reinforced Polymer Composites (NFRPC) are, cotton, sisal, coir, jute, hemp, flax, banana, bamboo etc. Several researches and publications on natural fibers and its composite show that despite the properties of these fibers, their applications were limited to non-structural applications either for interior or exterior applications just for their environmental and low-cost benefit with less concern for their strength capabilities. Sisal and jute are fibers from vegetable and bast plants that had been proved to have exhibited excellent tensile and flexural properties (bast composite) and best impact properties (vegetable composite), were also restricted to non-structural applications only. This paper reviewed the present status and future expectations of natural fiber reinforced composites in structural applications using sisal and jute fiber reinforced polymer composites as a case.
Abstract: Natural fibers that are mainly from plants, animals and regenerated sources are degradable and environmentally friendly as they absorb carbon dioxide and release oxygen, they are cost effective when compare to the synthetic fibers. These materials mainly from plant are used initially for domestics’ purposes. They have recently been introduced to so...
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A Practical Approach for Validation of Aptitude of Sized Carbon Fibers for the In-Mould -Impregnation Process
Andre Ullmer,
Tobias Kleffel,
Zhanyu Zhai,
Tobias Mattner,
Dietmar Drummer
Issue:
Volume 3, Issue 1, March 2019
Pages:
11-19
Received:
7 January 2019
Accepted:
19 February 2019
Published:
14 March 2019
Abstract: As a new and innovative processing method for carbon fiber reinforced thermoplastic composites, the In-Mould-Impregnation process (IMI) adopts carbon fibers as a heating element by electrical conduction. During heating of the dry carbon fibers in the production process, temperatures up to over 500°C can occur. However, the surface properties of carbon fibers and sizing may change under such conditions and thus affect the resulting composite. The present study is a practical approach to validate the suitability of sized carbon fibers for the IMI. The influence of a thermal treatment according to the parameters of the IMI-Process on carbon fiber-thermoplastic matrix interfacial adhesion was investigated by means of micromechanical and optical test methods. The experimental results demonstrate that the thermal treatment of carbon fibers causes a reduction of tensile strength of single fibers. It does not show an influence on the micromechanical breaking behavior in a PA 6 composite but the surface tension of carbon fibers changes. The change in surface tension can affect the wettability of the carbon fiber with a thermoplastic matrix.
Abstract: As a new and innovative processing method for carbon fiber reinforced thermoplastic composites, the In-Mould-Impregnation process (IMI) adopts carbon fibers as a heating element by electrical conduction. During heating of the dry carbon fibers in the production process, temperatures up to over 500°C can occur. However, the surface properties of car...
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Cause Analysis of Turbine Shaft Ultrasonic Flaw Detection Disqualification
Wang Yongsheng,
Sun Shengyu,
Sun Xin,
Guo Libo
Issue:
Volume 3, Issue 1, March 2019
Pages:
20-24
Received:
20 November 2018
Accepted:
27 May 2019
Published:
18 June 2019
Abstract: Heavy forging is a kind of large or deformed-size forge, used on marine, roller or power station roter. etc, which are fabricated by free forging or hydraulic compressor. The turbine shaft products, steel grade ASTM668E, rejected during ultrasonic inspection. Aiming at the problem of ultrasonic flaw detection disqualification, through Positioning saw cutting, the macroscopic test, SEM and Micrographic examination are taken out. The main cause of the disqualification were found out. The results show that, because of the exist of unbalance crystallization, highly grade general loosen happened in the cycle area, which cause the energy of ultrasonic are weakened a lot, then lead to the central quality of the forging cannot be detected clearly. What’s more, the manganese sulfide precipitated at the grain boundary because of the selective crystallization occurs in the central of the ingot. The tensile stress on the interface between steel and inclusion separate the steel, caused the cracks which couldn’t be welded as the plastic deformation happened in forging press, then cause the cracks. Reduce the molten steel’s overheat and the freezing time can improve the defect of general loosen and the gartering of low-melting ingredients. Increase the compression ratio can take out too in the hot work process to solve the problem.
Abstract: Heavy forging is a kind of large or deformed-size forge, used on marine, roller or power station roter. etc, which are fabricated by free forging or hydraulic compressor. The turbine shaft products, steel grade ASTM668E, rejected during ultrasonic inspection. Aiming at the problem of ultrasonic flaw detection disqualification, through Positioning s...
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