Abstract: A method for inspecting an additive manufacturing process in which a directed energy source is used to create a weld pool at an exposed build surface of a mass of powdered material, and selectively fuse the powdered material to form a workpiece. The inspection method includes: using a noncontact method to generate an acoustic wave in the build surface; using a noncontact method to measure displacement of the build surface in response to the acoustic wave; and determining at least one sub-surface material property of the workpiece by analyzing the displacement of the build surface.

Abstract: The present invention is related to additive manufacturing methods and systems using a recoater with in-situ exchangeable recoater blades. Being able to switch out recoater blades in situ, i.e. without stopping the build and opening up the build chamber, is advantageous, especially for larger, more complicated, and/or longer builds. For instance, if a recoater blade becomes damaged, a new one can be readily swapped in. Or if a different material for the object(s) is used during the build, it may be advantageous to switch in a new recoater blade that is made of the new, different material.

Abstract: In an aspect, the present disclosure relates to an apparatus for fabricating an object layer by layer. The apparatus includes a sheet dispenser to stack sheets of bound powder. The apparatus also includes a directed energy source configured to selectively fuse at least a portion of the bound powder to form one or more fused regions.

Abstract: Some aspects of the present disclosure provide a method of detecting defects in a continuous build process. The method includes applying a layer of powder to a build surface. The method includes fusing at least a portion of the powder layer to form a portion of a part. The method includes detecting a particular band of electromagnetic radiation produced by the fusing. In an aspect, the particular band of electromagnetic radiation is ultraviolet (UV) radiation.

Abstract: A method of monitoring an additive manufacturing process in which a directed energy source is used to create a weld pool at an exposed build surface of a mass of powdered material, and selectively fuse the powdered material to form a workpiece, the method including measuring acoustic energy generated by the weld pool to generate a measured acoustic profile.

Abstract: A method of monitoring laser power in an additive manufacturing process in which a build beam generated by a laser source is used to selectively fuse or cure material to form a workpiece. The method includes: splitting off a predetermined percentage of the build beam to define a sample beam, and directing the sample beam to a sensor; using the sensor to generate a signal proportional to the power of the sample beam; and scaling the signal from the sensor to generate a laser power measurement representative of a power level of the build beam.

Abstract: A method of monitoring an additive manufacturing process in which a directed energy source is used to create a weld pool at an exposed build surface of a mass of powdered material, and selectively fuse the powdered material to form a workpiece, the method including measuring acoustic energy generated by the weld pool to generate a measured acoustic profile.

Abstract: A method for inspecting an additive manufacturing process in which a directed energy source is used to create a weld pool at an exposed build surface of a mass of powdered material, and selectively fuse the powdered material to form a workpiece. The inspection method includes: using a noncontact method to generate an acoustic wave in the build surface; using a noncontact method to measure displacement of the build surface in response to the acoustic wave; and determining at least one sub-surface material property of the workpiece by analyzing the displacement of the build surface.