Top 5 Challenges of Composite-Based Aerospace Design
Aerospace design is a complex enterprise in and of itself. It is made more complex when composites are introduced into the equation. Why? Because aerospace composites open the door to more advanced designs that simply are not possible with traditional materials. The more advanced the design becomes, the more complex it is.
Our partners in aerospace rely on everything from phenolic prepregs to epoxy film adhesives and honeycomb core composites. They work with fiberglass, carbon fiber, and other materials. But regardless of the details of each design, every engineer runs into the same challenges.
1. Material Selection
The broader arena of aerospace composites offers engineers a lot of choices. They must carefully choose the appropriate combination of fiber and matrix materials in order to meet performance requirements. But material selection is not as easy as selecting a carbon fiber fabric and the cheapest epoxy resin to go with it.
Composite materials offer unique properties and behaviors. Even materials starting with the same base, like carbon fiber, may behave differently in a given application. Engineers need to think long and hard to ensure they are marrying the right fibers with the right matrices.
2. Design Complexity
One of the reasons composite materials are so desirable in aerospace engineering is that they are suitable even for complex designs. But it is one thing to design a complex part on paper. It’s another thing entirely to manufacture that part.
Design complexity impacts manufacturing techniques. It also influences component performance, structural integrity, and maintenance requirements. Engineers must be careful not to introduce complexity just for the sake of doing so. If a more complex design doesn’t offer enough benefits, it might not be worth pursuing.
3. Manufacturing Costs
As fantastic as aerospace composites are, one of their drawbacks is cost. Phenolic prepregs and honeycomb structures just cost more than steel and aluminum. More importantly, composite manufacturing is more costly on a per-process basis.
Everything from specialized equipment to skilled labor to intense energy needs makes manufacturing with composites more expensive. Engineers need to justify the expenses every time they introduce a new design.
4. Product Behavior and Limitations
Every material an engineer chooses to work with comes with behavior specifications and limitations. Engineers need to be intimately familiar with how materials behave at rest and under load. They need to understand material limitations in order to avoid pushing designs too far.
For example, composite materials tend to become weak and brittle at extremely low temperatures. As a result, certain composites just aren’t appropriate for certain applications.
5. Quality Control
It goes without saying that quality control is non-negotiable in aerospace design. The last thing anybody wants to see is a catastrophic failure in midair. We have seen far too many such failures in the past. Fortunately, composite-based aerospace design has helped us reduce catastrophic failures over the years.
For the engineer, quality control must be built into the manufacturing process. Each composite material must pass stringent quality control measures before it can be deployed in a project. Likewise, the finished part must undergo rigorous quality control testing.
An Emerging Challenge
The final challenge, multifunctional integration, has only recently emerged. Engineers are facing it as they attempt to fully integrate composites with multifunctional applications. Successful integration can meet evermore complex design needs.
Aerospace design has never been a walk in the park. But with the capabilities afforded through aerospace composites, design seems to be more challenging by the year. We are guessing that aerospace designers and engineers don’t mind a bit. The challenges of building better and faster aircraft motivate them to do what they do.