Integrating ultrasound transducers in polymer additive manufacturing technologies to fabricate engineered composite materials with tailored properties

Abstract

Engineered composite materials that comprise filler material embedded in a polymer matrix may exhibit exotic physical properties that derive from the specific type, geometry, organization, and orientation of the particles in the matrix. However, existing techniques to manufacture such engineered materials are limited to laboratory scale, specific materials, and/or 2-D implementations, because it is challenging to organize and orient large quantities of particles into specific patterns. We utilize the acoustic radiation force associated with a standing ultrasound wave field to organize and orient particles of any material type dispersed in a fluid medium, into a user-specified pattern. We integrate the ultrasound wave field with several polymer additive manufacturing technologies to manufacture engineered materials in a layer-by-layer fashion, where in each layer we organize a user-specified pattern of filler using the acoustic radiation force. We demonstrate and discuss the integration of ultrasound transducers with several AM technologies and highlight their operating envelope and limitations. This research finds application in 3-D printing engineered materials with tailored properties by tuning the geometry, surface area, local packing density and, thus, the properties of the material.