Utilizing 3-D woven composite structures in place of traditional metal or 2-D laminated composites can provide cost savings through both the manufacturing process and a product’s operational lifetime. In this blog, we’ll answer some basic questions about the emerging technology – and why it’s useful for a wide variety of applications
What allows 3-D weaving to produce strong, complex, single-piece structures?
Most fabrics are woven in two dimensions – the X axis (length) and the Y axis (width) – but 3-D woven fabrics include weaving through the thickness, or the Z axis. By contrast, 2-D composites include a number of different layers of materials artificially bonded together; these layers can come apart from each other, or delaminate. 3-D weaving produces near-net-shape composite structures that are fully interconnected by their yarn, ensuring they retain strength and reliability.
What are some of the benefits of 3-D woven composites?
In addition to the elimination of delamination, the technology’s key benefits include weight reduction, reduced crack risk, lower production time, and cost reduction.
Lightweight. 3-D woven composites are dramatically lighter than metal structures. This is particularly relevant to the aerospace industry. Every pound of weight saved from an aircraft is estimated to save the aircraft’s operator roughly $1 million in operating expenses, primarily fuel, over that aircraft’s lifetime. Smart utilization of 3-D woven composite structures in aircraft design can reduce the weight of an aircraft by up to 30 percent, resulting in considerable operational cost savings.
Low crack risk. Due to curvature limitations in the layers, many 2-D shapes have considerable gaps in joints and intersections. These spaces and pockets are often filled with resin, which can crack. 3-D woven composites, even in complex shapes, have no empty pockets, as their structural integrity extends along all three axes. Crack rates are therefore far lower.
Quick production. 2-D composite production entails a long plying process. By contrast, 3-D weaving of composite structures is simpler, faster, and more cost efficient. The difference in a 3-D loom is that weft and warp yarns are not only woven together on one plane, but one plane is woven together with the next. Aside from designing a 3-D weave, which requires highly skilled design engineers, the 3-D weaving process is fully automated, drastically reducing manufacturing time.
Low cost. Indirect cost savings result from operational cost savings, for example reduced fuel. Plus, 3-D woven composites are stronger, more resilient, and less prone to breakage than 2-D laminated composites, so they can be replaced much less often, reducing replacement and maintenance costs.
What are some uses for 3-D woven structures?
3-D woven composites including orthogonal panels, thermal protection systems, near-net-shape, and complex net shape preforms are used for the aerospace, automotive, construction, military, and safety industries. For example, carbon fiber composites replace traditional titanium components in large aircraft engines to reduce weight, as these composite components are significantly lighter than comparable components in metal.
3-D weaving has been particularly successful in advancing aviation heat shield technology. BRM has woven quartz compression pads for NASA’s Orion capsule in order to ensure structural strength during launch and heat resistance during re-entry. NASA’s Heatshield for Extreme Entry Environment Technology (HEEET) program is developing a carbon thermal protection system (TPS) for extreme entries, intended to be capable of surviving the challenging environments of Saturn or Venus.
By Mark Harries
For more information about 3-D woven composites, and how they could improve your design, contact BRM today.