Layer manufacturing using deposition of fused droplets

Abstract

A solid freeform fabrication process and apparatus for making a three-dimensional object. The process comprises the steps of (1) positioning a material deposition sub-system a selected distance from a target surface, (2) operating this sub-system to deposit materials onto the target surface by carrying out the sub-steps of (a) operating a multiple-channel powder delivery device for supplying selected powder compositions at a predetermined flow rate to travel toward the target surface and (b) operating a focused energy beam to produce a fusion zone through which the powder particles, preferably in micron or nanometer sizes, are melted while in flight, thereby producing liquid droplets traveling to deposit onto the target surface, and (3) during the material deposition process, moving the deposition sub-system and the target surface relative to one another along selected directions in a plane defined by first and second coordinate directions and in a third direction orthogonal to this plane to form deposition materials into a three dimensional shape. These steps are preferably executed under the control of a computer system. Preferably, the system is also operated to generate a support structure for any un-supported feature of the object.