LOW ENERGY PROCESS FOR MAKING CURVED SANDWICH STRUCTURES WITH LITTLE OR NO RESIDUAL STRESS

摘要

A process for fabricating a curved beam including a micro-truss structure. In one embodiment, the process includes fabricating the micro-truss structure on a bottom facesheet, where the micro-truss structure is only partially cured so that it is readily bendable, and then forming the partially cured micro-truss structure and bottom facesheet over a curved fixture, where the partially cured micro-truss structure is then fully cured and hardened to its final curved state. A top facesheet is then adhered to a top surface of the micro-truss structure. In an alternate embodiment, a curved bottom facesheet is forced flat against a fixture and the micro-truss structure is formed while the bottom facesheet is secured to the fixture to a partially cured state. The bottom facesheet is then released from the fixture, which causes it to return to its curved configuration causing the micro-truss structure to bend.

主权项

1. A method for fabricating a curved sandwich structure, said method comprising:
providing a flat bottom facesheet; positioning a mold in contact with the bottom facesheet so that the mold and the bottom facesheet define an enclosure; filling the enclosure with a liquid photo-monomer resin; positioning a mask with patterned apertures relative to the mold; irradiating the liquid photo-monomer resin in the enclosure through the apertures in the mask with collimated UV light from a plurality of sources to form a partially cured micro-truss structure having a plurality of interconnected self-propagating photopolymer waveguides in a lattice configuration coupled to the bottom facesheet; removing uncured liquid photo-monomer resin from the mold; removing the mold from the partially cured micro-truss structure and the bottom facesheet; conforming the bottom facesheet to a curved fixture so that the bottom facesheet is bent to the shape of the curved fixture and the partially cured micro-truss structure bends in association with the bottom facesheet; fully curing the micro-truss structure to a rigid state while it is conformed to the shape of the fixture; and attaching a top facesheet having a complimentary curvature to the now curved micro-truss structure and bottom facesheet to form the sandwich structure.