Research team looks to fabricate preforms for composites

New study looks at opportunities and challenges of additive manufacturing for composite processing.

Researchers at the University of Delaware are examining the feasibility of using additive manufacturing to produce 3D preforms for composites.

In traditional processes, complex parts are usually built by assembling separate simple parts, which can lead to premature structural failure at material joints. Additive manufacturing allows an object to be built up layer by layer from a computerized model.

The technique enables direct fabrication of complex-shaped objects without tooling and machining, and it also eliminates the need to join a number of single parts into a single complex one. 

Another advantage of this technology is that material composition can be changed at specified locations within a part at the processing stage, enabling various functions and graded properties to be incorporated directly during manufacturing. 

In additive manufacturing, the material is placed just where it is needed, and the residual material can often be readily recycled or reused, reducing material waste. 

“All of these features make additive manufacturing an attractive option for composite materials development,” said the University of Delaware’s Tsu-Wei Chou. Their work is documented in a paper published in Materials Today. The paper discusses challenges facing the broad adoption of additive manufacturing for directionally reinforced composites processing. 

Those challenges include the need for new CAD tools and engineering standards, difficulties in process monitoring, and limitations in part size, printing accuracy, layer thickness and surface smoothness.

Despite these limitations, Chou says he sees great potential in additive manufacturing of fiber-reinforced preforms, which, he says, are especially desirable for composite parts in aerospace and biomedical applications.