Role Of Composite Materials Research Articles

Fillers preparation for polymer composite and its properties – a review

This paper is a review about the manufacture of polymer matrix composite by the filler materials, property and its preparation. Day by day the role of composite materials in industrial and household applications is increased. By using the variety of matrix, reinforcement and filler materials the polymer composite obtains from it. To improve the mechanical properties of the polymer composite, important role is played by filler materials. There is a unique property for each type of filler materials, which is altered by changing the percentage of filler materials. Filler materials important purpose is to reduce the cost of material and it increase the mechanical properties, that also use to increase surface finish and thermal property. In this paper, the elaboration of polymer materials and its uses are discussed, which held later the synthesis of polymer composite by different fillers. The filler properties, manufacture methods, polymer composite properties are discussed.

A mathematical modeling approach to optimize composite parts placement in autoclave

AbstractThe role of composite materials in the development of new advanced products for many industrial applications is strictly dependent on the reduction of materials and processing costs. High‐performance composites are usually manufactured utilizing prepregs for lamination and an autoclave, where the curing process of the thermosetting matrix is completed by increasing temperature and pressure. Several composite parts are commonly cured in the same autoclave leading to nonuniform thermal histories, which depend on their position inside the autoclave, and on the thermal inertia of parts. In this paper, we propose a mixed integer linear programming model to optimize the composite part placement into an autoclave. The main decision variables determine the orientation and placement of parts in the autoclave, while the objective function is formulated to minimize the maximum overexposure of the curing process. The validity for practical use of our model has been tested on a set of real cases.

Mimicking Bone Structure and Function with Structural Composite Materials

This paper reviews the progress that has been made in fabricating biomimetic bone structures using synthetic composite materials. The specification for long bone applications is developed and we identify the candidate materials for delivering cortical and cancellous bone properties and function. The role of composite materials is discussed together with the factors influencing fibre and matrix type. Challenges associated with moderating their performance in-vivo are discussed, relating to the properties of the starting materials and the dependence, for fibre reinforced systems, on interface quality. Fabrication routes for producing complex biomimetic structures are also reviewed and the state of current clinical developments is described along with the associated technical and regulatory issues.

Blistering of Moisture Saturated Graphite/Polyimide Composites Due to Rapid Heating

Polyimide matrices extend the role of composite materials to applications in extreme temperature environments. However, composites can be susceptible to damage under extreme hygrothermal environments such as rapid heating of moisture saturated materials. Here, rapid is defined as reaching high temperature in less than the drying time at that temperature. A new method to predict initiation of steam-pressure induced damage for rapidly heated neat resin and graphite/polyimide composites is proposed. This method entails comparing the calculated, available steam pressure within the laminate to an experimentally determined critical pressure—temperature envelope. Through experiments performed in a thermal mechanical analyzer it is shown that the onset of steam-induced damage can be detected by measuring the expansion of moisture-saturated specimens subjected to a rapid temperature ramp. Optical microscopy of damaged samples shows that the process of initiation and evolution of damage in neat resin and laminates begins with void growth and coalescence in the polyimide resin matrix. Data from tests performed over a range of heating rates and initial moisture saturations are used to develop a critical pressure—temperature envelope. With this envelope we show the dependence of damage on initial moisture content and heating rate and propose an application of this envelope to failure prediction and design of laminated structures subjected to rapid heating.

The cause and consequences of a satellite fragmentation: A case study

The fragmentation of a Pegasus Hydrazine Auxiliary Propulsion System upper stage on 3 June 1996 stands as the worst satellite breakup on record in terms of cataloged orbital debris. In addition to the more than 700 debris large enough to be tracked (approximately 10 cm in diameter or greater) in the 200 km by 2,000 km orbital regime by the U.S. Space Surveillance Network, a debris population of up to 300,000 objects larger than 4 mm appears to have been generated, based upon special radar observations. The debris cloud presented an immediate threat to many resident space objects, such as the Hubble Space Telescope, which resided in an orbit just 25 km below the breakup altitude. Special analyses were required to ensure the safety of the STS-82 Hubble Space Telescope servicing mission in February 1997. This paper describes the activities undertaken at the National Aeronautics and Space Administration Lyndon B. Johnson Space Center to characterize the near-term and far-term hazard of the debris cloud to manned and robotic spacecraft and to investigate the probable cause of the accident. The role of composite materials in the vehicle may have led to the creation of a much larger number of debris than would have been expected from a more conventional upper stage. To avoid a repetition of the incident, the Hydrazine Auxiliary Propulsion System upper stage was modified before its next launch, and additional passivation measures were adopted. This fragmentation event represents a textbook case for the hazards posed by satellite breakups and how fragmentation potential can be reduced without significantly affecting the capability of the vehicle.

Role of composite materials in a functional approach to miniaturisation in electronics

This paper highlights the significance of a functional approach to miniaturisation of electronic systems. It is shown that multi-phase composite materials can provide exciting opportunities to develop new functional components which ultimately can result in miniaturisation. As an illustration, variable resistors with positive resistance coefficient are described in detail.

The role of composite materials in the future

The role of composite materials in the future

The role of composite materials in the future

The role of composite materials in the future