Patent ID: 11904533
Assignee: THE BOEING COMPANY
Field: Chemical engineering (Chemistry)
Classification: CPC B  C  G  H  Y | IPC B  C  G

Claim 11:
12. A method of fabricating an object by fused powder fabrication, the method comprising:
forming a coated powder by:
advancing a plurality of powder particles through a chamber, each of the plurality of powder particles being formed of a base polymer material having a first dielectric loss factor with a first tan value in a predefined microwave frequency range;
applying a liquid coating to an exterior of each of the plurality of powder particles, the liquid coating being formed of a coating polymer material distinct from the base polymer and having a second dielectric loss factor with a second tan value in the predefined microwave frequency range, the second tan value being at least about 50 times larger than the first tan value of the base polymer material and thereby more susceptible to heating in response to electromagnetic energy than the base polymer material; and
drying the liquid coating on the plurality of powder particles to form a plurality of coated powder particles, wherein each of the plurality of coated powder particles comprises a base polymer layer formed by the powder particle and a coating polymer layer formed by the liquid coating after drying the liquid coating;
depositing the coated powder in a first build layer on a substrate;
heating selected portions of the first build layer;
depositing the coated powder in a second build layer on the substrate and over the first build layer;
heating selected portions of the second build layer; and
dielectrically heating the coating polymer layer of the coated powder in the selected portions of the first and second build layers using electromagnetic radiation to thereby fuse adjacent particles of the coated powder across an interface area.