Role of thermoplastic composites in next generation Aerospace
As a prominent material for aerospace applications in the future, advanced thermoplastic composites are triggering a series of activities of Aerospace Manufacturers, designers, component manufacturers and molding processors. The research and development of thermoplastic composites for aerospace is accelerating, and more tests are being carried out on thermoplastic composites.
Some new companies are also entering the market, gaining supplier qualifications from Aerospace Manufacturers and strengthening existing supply chains. The innovative manufacturing methods of thermoplastic are being developed, improved and put on line. All of these indications indicate that the application of thermoplastic materials in the next generation of commercial aircraft and related applications will be greatly increased.
The progress of the production, forming and manufacturing of thermoplastic materials has become the main factor for the increasing of thermoplastic materials. In some aerospace applications, these materials have obvious advantages over thermosetting plastics and aluminum. They also coincide with the emerging trends of aerospace manufacturing, including the acceleration of aircraft assembly and production speed, and the development of advanced commercial aircraft design.
Analysis of the advantages of thermoplastic composites for Aerospace
Aerospace grade thermoplastic composites, such as carbon fiber reinforced polyetherketone (PEEK) and polyether ketone (PEKK), have the most promising applications in the field of modern aerospace. Thermoplastic prepreg is produced on the main roller and can be converted into slit strip, short cut fiber or other forms. These products are optimized to achieve efficient and increasingly streamlined parts production.
Aerospace grade thermoplastic has light and high temperature resistance, and has high toughness and impact resistance. Other key features include:
Low moisture absorption
Excellent wear resistance
Excellent flame / smoke toxicity
Low emission of volatile chemicals
Low thermal cycle expansion coefficient
Although the supply chain of thermosetting plastics is more perfect and the application history of aerospace structural parts is longer, the recent technological and technological development is improving the competition pattern of thermoplastic materials. For example, manufacturers and precision molding processors are improving the accuracy of the cutting and conversion process to produce more types of advanced components.
Thermoplastic and thermosetting plastics have similar properties, but they have significant differences in processing and treatment requirements. Although thermoplastic requires higher processing temperatures than thermosetting plastics, they can be stored at room temperature and have almost unlimited shelf life.
In contrast, thermosetting plastics must be frozen and thawed before processing in order to maintain their mechanical properties during transportation and storage. The required shelf life, time required for thawing and freezing, and the need to track the total freezing time and thawing time, all of which are added up to an additional cost unrelated to thermoplastic.
Thermoplastic materials have the advantages of recycling. Unlike thermosetting plastics, thermosetting plastics can undergo irreversible chemical reactions during processing, and they cannot be melted again. Thermoplastic can be reprocessed after use, so that thermoplastic resin and reinforced fiber can be recycled or reused for other applications.
Design of new generation aerospace grade composite materials
Advanced thermoplastic composites provide an extended material toolbox for the designers of the next generation aircraft. Thermoplastic makes aircraft design more creative and flexible. They can form complex profiles and shapes that allow aircraft to be shaped, not machined. Thermoplastic composite materials are currently used for semi structural components such as clamps and supports, but the main structural components such as fuselage panel, wing box and longitudinal beam are under test.
The next generation of aerospace design will require faster manufacturing and assembly. The manufacturing speed of thermoplastic parts is very consistent with the expected needs of aircraft manufacturers and designers. Consider the use of automatic fiber to lay the fuselage part of the production. If the part is made of thermosetting material, the part must be pressurized and cured in a autoclave after lamination. In contrast, thermoplastic materials can be reinforced by advanced heat treatment, thus reducing the manufacturing time required for aircraft production.
The use of thermoplastic materials also helps reduce the number of headquarters components of the aircraft. This material can weld adjacent parts together without changing the dimensional tolerance, thus eliminating the need for many small fasteners.
In addition to commercial aircraft, thermoplastic materials can also be used in demanding satellite applications. In a practical application case, a company provided a thermoplastic slit tape to a satellite manufacturer with very smooth edges and dimensional tolerance beyond industry standards for its proprietary process.
The component is light weight and is an ideal choice for launch vehicle and payload. Once in space, it maintains its stiffness when it expands. Due to the low coefficient of thermal expansion, the material is stable in size when the satellite experiences thermal cycle.
Precise format of production and processing
The main manufacturing methods for producing thermoplastic parts include automatic fiber placement / automatic tape laying (afp/atl), continuous compression molding, discontinuous compression molding and automatic pressing / hot forming. Each method is designed for some types of aerospace components and requires prepreg customized for this purpose.
For example, continuous compression molding requires placement of directional material on the spooling spool or pad, while afp/atl uses slit tape. The precision formatter provides the precise level of the conversion material, saving Aerospace Manufacturers time and cost.
Thermoplastic slit tape (left) is used in the laying and manufacturing process of precision fiber, while the cut material (right) is used for discontinuous compression molding applications
Even though the processing and manufacturing technology of thermoplastic composites is developing and improving, the research and development of thermosetting materials and aerospace metals are still continuing, and they are also improving. Therefore, no one material will be the dominant material in aerospace applications in the future, but considering many advantages of advanced thermoplastic, they are likely to play an increasingly important role in the next few years.