Browse Topic: Advanced composite materials
The intent of this specification is for the procurement of carbon fiber and fiberglass epoxy prepreg products with 350 °F (177 °C) cure for aerospace applications; therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program must refer to the production quality assurance section (4.3) of this base specification, AMS6891.
The intent of this specification is for the procurement of the material listed on the QPL; therefore, no qualification or equivalency threshold values are provided. Users that intend to conduct a new material qualification or equivalency program must refer to the Quality Assurance section of the base specification, AMS6891.
Innovators at the NASA Glenn Research Center have developed a toughened hybrid reinforcement material made from carbon fiber and carbon nanotube (CNT) yarn for use in polymer matrix composites (PMCs). The new material improves toughness and damping properties of PMCs, enhancing impact resistance, fatigue life, as well as structural longevity.
Disc brakes play a vital role in automotive braking systems, offering a dependable and effective means of decelerating or halting a vehicle. The disc brake assembly functions by converting the vehicle's kinetic energy into thermal energy through friction. The performances of the brake assembly and user experience are significantly impacted by squeal noise and wear behaviour. This paper delves into the fundamental mechanisms behind squeal noise and assesses the wear performance of the disc brake assembly. Functionally graded materials (FGMs) are an innovative type of composite material, characterized by gradual variations in composition and structure throughout their volume, leading to changes in properties such as mechanical strength, thermal conductivity, and corrosion resistance. FGMs have emerged as a groundbreaking solution in the design and manufacturing of brake rotors, addressing significant challenges related to thermal stress, wear resistance, and overall performance. These
To save on fuel and reduce aircraft emissions, engineers are looking to build lighter, stronger airplanes out of advanced composites. These engineered materials are made from high-performance fibers that are embedded in polymer sheets. The sheets can be stacked and pressed into one multilayered material and made into extremely lightweight and durable structures.
The future of space travel is seemingly changing by the day and a Coventry University academic is doing his bit to stay at the front of the space race.
In research that may lead to advancements in the design of next-generation airplane and spacecraft, MIT engineers used carbon nanotubes to prevent cracking in multilayered composites. Massachusetts Institute of Technology, Cambridge, MA To save on fuel and reduce aircraft emissions, engineers are looking to build lighter, stronger airplanes out of advanced composites. These engineered materials are made from high-performance fibers that are embedded in polymer sheets. The sheets can be stacked and pressed into one multilayered material and made into extremely lightweight and durable structures. But composite materials have one main vulnerability: the space between layers, which is typically filled with polymer “glue” to bond the layers together. In the event of an impact or strike, cracks can easily spread between layers and weaken the material, even though there may be no visible damage to the layers themselves. Over time, as these hidden cracks spread between layers, the composite
To save on fuel and reduce aircraft emissions, engineers are looking to build lighter, stronger airplanes out of advanced composites. These engineered materials are made from high-performance fibers that are embedded in polymer sheets. The sheets can be stacked and pressed into one multilayered material and made into extremely lightweight and durable structures.
Composite materials play an important role in aerospace manufacturing. The light weight, durability and ability to create complex shapes from molds make these materials ideal for frames and structural components that enable lighter, more fuel-efficient aircraft. While composite structures can weigh up to 20 percent less than their metal counterparts, these materials can often be more difficult to machine. The extremely abrasive nature of carbon fiber reinforced polymers (CFRPs) will wear down standard cutting tools more quickly than almost any other material. A standard carbide cutting tool may only hold up to cutting a few feet of CFRPs before its dimensional stability fails, while in traditional metal machining that same tool might last 20 to 50 times that before wearing out.
Additive manufacturing (AM) is currently being used to produce many aerospace components, with its inherent design flexibility enabling an array of unique and novel possibilities. But, in order to grow the application space of polymer AM, the industry has to provide an offering with improved mechanical properties. Several entities are working toward introducing continuous fibers embedded into either a thermoplastic or thermoset resin system. This approach can enable significant improvement in mechanical properties and could be what is needed to open new and exciting applications within the aerospace industry. However, as the technology begins to mature, there are a couple of unsettled issues that are beginning to come to light. The most common question raised is whether composite AM can achieve the performance of traditional composite manufacturing. If AM cannot reach this level, is there enough application potential to warrant the development investment? The answers are highly
Recycling of advanced composites made from carbon fibers in epoxy resins is required for two primary reasons. First, the energy necessary to produce carbon fibers is very high and therefore reusing these fibers could greatly reduce the lifecycle energy of components which use them. Second, if the material is allowed to break down in the environment, it will contribute to the growing presence of microplastics and other synthetic pollutants. Currently, recycling and safe methods of disposal typically do not aim for full circularity, but rather separate fibers for successive downcycling while combusting the matrix in a clean burning process. Breakdown of the matrix, without damaging the carbon fibers, can be achieved by pyrolysis, fluidized bed processes, or chemical solvolysis. The major challenge is to align fibers into unidirectional tows of real value in high-performance composites.
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