Composite materials have modernized aerospace engineering by combining exceptional strength with lightweight properties.
Today, three main types dominate the industry: carbon fiber, glass fiber, and aramid-reinforced composites. From aircraft wings and fuselage sections to engine components and satellite structures, these materials have reduced fuel consumption while improving performance. Their superior strength-to-weight ratio, durability, and thermal resistance make them essential for modern aviation and space exploration.
But in an industry where safety regulations and standards are so important, it is critical that materials used to build an aircraft or spacecraft can withhold the pressure put on them. However, due to the nature of their composition, composite materials can exhibit complex behaviors that can be difficult to predict, especially under varying conditions such as temperature and stress. This unpredictability necessitates extensive testing and simulation to ensure reliability and performance.
Read on to understand more about how and where composite materials are used in aerospace manufacturing, and the role that simulation software can play in ensuring parts adhere to the strict standards required of them…
Composite materials offer numerous advantages over traditional metals like aluminum and steel. Carbon fiber-reinforced polymers (CFRP) and other composites provide a unique combination of strength, durability, and lightweight properties that contribute to the efficiency and performance of aircraft.
One of the most significant benefits of composites is weight reduction. By using these lightweight materials, aircraft manufacturers can improve fuel efficiency and reduce operating costs. Composites also deliver exceptional strength-to-weight ratios, making them ideal for structural components where both rigidity and reduced mass are essential. Unlike metals, composites are naturally corrosion-resistant, ensuring longer component lifespans even in harsh environments.
Additionally, composites offer unparalleled design flexibility. Their moldability allows manufacturers to create complex, aerodynamic shapes and consolidate multiple parts into a single piece, reducing assembly time and cost. Engineers can also customize the thermal and electrical properties of composites, tailoring them to meet the functional requirements of various aerospace applications.
Modern aircraft design relies heavily on CFRP, with materials comprising up to 50% of newer aircraft structures.
These advanced composites blend carbon fibers with sophisticated polymer matrices, creating materials that outperform traditional aerospace metals. Engineers can tailor CFRP properties by adjusting fiber orientation and matrix composition, enabling precise control over stiffness and strength in specific directions.
The manufacturing versatility of CFRP allows for complex shapes and integrated structures, reducing the number of parts and fasteners required. This characteristic proves particularly valuable in creating seamless aerodynamic surfaces for enhanced performance.
The E-glass and S-glass variants serve distinct roles in modern aircraft construction. E-glass (E stands for electrical) dominates interior components like cabin flooring and cargo liners due to its excellent electrical insulation properties and cost-effectiveness. Meanwhile, S-glass (S stands for Silica contents, able to withstand high temperatures) finds its place in more demanding applications, particularly in helicopter rotor blades and aircraft empennages.
The development of GLARE (Glass-Reinforced Aluminum), which combines glass fiber layers with aluminum sheets, has led to weight reductions of up to 40% in certain applications compared to traditional aluminum structures.
Glass fiber composites excel in protecting aircraft against lightning strikes and electromagnetic interference, making them indispensable for modern aviation safety systems.
Aramid fiber composites bring exceptional impact resistance and vibration dampening capabilities to aerospace structures. These materials excel in areas requiring superior damage tolerance, such as helicopter rotor blades and aircraft landing gear components.
The material's remarkable fatigue resistance makes it perfect for dynamic aerospace parts experiencing repeated stress cycles. For example, leading manufacturers incorporate aramid-based composites in cargo hold floors and protective panels, where their durability proves invaluable.
The combination of aramid with other fibers produces hybrid composites that maximize strength while minimizing weight in critical aerospace components.
Composite materials are extensively used in both primary and secondary aerospace structures. For primary structures, such as fuselages, wings, and tail sections—composites are chosen for their strength, durability, and corrosion resistance, all of which are critical for load-bearing components. At the same time, their lightweight nature contributes to significant weight reduction and improved fuel efficiency. For secondary structures, including interior panels, seat frames, and fairings, the focus is primarily on minimizing weight, where composites offer a practical balance of lightness and durability.
In jet engines, composite fan blades and casings reduce weight and enhance fuel efficiency while also dampening noise and vibrations. Engine nacelles, which encase the engine, are often made from composites to ensure aerodynamic performance and structural protection.
Spacecraft and satellites also rely heavily on composites. Solar panels, antennae, and structural elements are constructed from composite materials due to their resilience in extreme temperatures and radiation exposure. Additionally, in propulsion systems, rocket nozzles and fuel tanks utilize composites for their high strength and thermal resistance, essential for enduring the intense conditions of launch and space travel.
Due to the material’s complex nature and the stringent performance requirements of the industry, manufacturing composite materials is not always straightforward.
One significant problem is the precise handling and layup of composites, as they are sensitive to environmental conditions like humidity and temperature. Accurate fiber placement is crucial to prevent defects such as wrinkles, voids, or misalignment, which can compromise structural integrity. Automated systems like Automated Fiber Placement (AFP) are often used to enhance accuracy, but even minor deviations can lead to performance issues.
The curing process also poses difficulties. Composites require controlled heating and pressure, often in an autoclave, to harden the resin matrix. Inadequate curing can lead to incomplete polymerization, creating brittle or weak components. Additionally, improper temperature control may cause residual stresses, resulting in warping or cracking. Manufacturers often rely on simulation software to predict and prevent these issues, ensuring components meet quality standards.
Detecting defects in composites is another challenge. Internal flaws like delamination, porosity, or fiber waviness can occur without visible signs. Sophisticated non-destructive testing (NDT) methods, including ultrasonic testing and X-ray imaging, are essential for quality control. However, these inspections increase production costs and time, making defect prevention through process optimization a priority.
Tooling variability presents additional difficulties. Composite components often require custom molds and fixtures, adding to production expenses. Variations in material properties can also affect consistency, requiring manufacturers to implement real-time monitoring and adaptive processing to maintain product quality.
Finally, environmental concerns remain a significant challenge. Most composites use thermoset resins that are difficult to recycle, contributing to waste. Additionally, the energy-intensive curing process increases carbon emissions. Research into recyclable thermoplastics and sustainable composite materials is ongoing to mitigate these environmental impacts.
Addressing the above challenges requires advanced technologies, robust simulations, and continuous innovation. By improving material selection, refining manufacturing processes, and utilizing digital tools, aerospace manufacturers can produce reliable, high-performance composite components that meet the industry's demanding standards.
To maximize the benefits of composite materials and address the challenges previously outlined, aerospace manufacturers are heavily relying on simulation software. These virtual tools streamline the design, manufacturing, and optimization processes, helping engineers predict material behavior, reduce defects, and accelerate development cycles.
Let’s take a closer look at how composite (manufacturing and performance) simulation tools can contribute to solving some of the key challenges related to composites engineering.
Simulation software can predict how composites will perform under mechanical loads, temperature fluctuations, and environmental factors. Engineers can analyze strength, stiffness, and durability to determine the best material layup for specific applications.
Manufacturing with composites can introduce challenges like wrinkles, voids, or fiber misalignment. Simulation tools detect these potential defects during draping, forming, injection, infusion and curing processes. By identifying and resolving issues before production, companies minimize costly rework and material waste.
Virtual validation reduces the need for physical prototypes, expediting the transition from design to production. This significantly shortens time-to-market while ensuring that components meet the rigorous aerospace standards.
Simulation software optimizes critical processes such as draping, forming, thermoforming, resin transfer molding (RTM), VARI (vacuum assisted infusion), CRTM (Compression RTM), and curing (in autoclave or OOA). Engineers can refine process parameters to minimize cycle times, reduce energy consumption, and enhance overall production efficiency.
Aerospace parts must withstand extreme operational conditions, including high stress and fatigue. Simulation enables engineers to predict how composite structures will perform under real-world scenarios, ensuring components meet safety and performance standards.
By simulating mechanical behavior, engineers can confidently reduce wall thickness and component weight without sacrificing strength. Simulation also supports the development of intricate geometries and integrated designs that would be difficult to achieve using traditional methods.
Accurate virtual prototypes for manufacturing and structural performance minimize the reliance on trial-and-error, reducing material waste and tooling expenses. Manufacturers benefit from more efficient production planning and a streamlined path to certification.
PAM-COMPOSITES from ESI enables manufacturers to study each step of the composites manufacturing chain, draping/forming, injection/infusion and curing/distortion, through a process-oriented workflow. Material information and history (local shearing, local fiber content, and orientation, degree of cure, etc.), as well as geometrical properties (shape, thickness, etc.), are transferred from one stage of the manufacturing chain to the next. This ensures maximum feedback accuracy when adjusting the process parameters to correct defects and reduce production cycle time.
Once the process chain is optimized to meet product tolerances, results can be transferred to product design for an “as-built” instead of “as-designed” structural analysis. This approach minimizes design margins and improves weight reduction.
Composite simulation software is a critical enabler for the aerospace industry, allowing manufacturers to design lighter, stronger, and more efficient components while reducing costs and development times. By addressing the complexities of composite materials and processes, these tools help aerospace companies meet the demands of innovation, sustainability, and safety in a highly competitive market.
Visit the PAM-COMPOSITES webpage to find out more.
Katharine Edmonds is a Content Marketing Specialist at ESI Group, and has spent the past 9 years working in marketing and communications for SaaS providers in the engineering and manufacturing industries. Katharine leans on her knowledge and experience of CAD, PLM and eXtended Reality (XR) technologies to create engaging and informative content that champions the benefits of virtual prototyping, and bridges the gap between complex technical subjects and a broader audience.