Abstract: An additive manufacturing apparatus for producing a three-dimensional object includes a process chamber for building the object. The process chamber includes the build area and a ceiling of the process chamber located opposite the build area, and a nozzle element is arranged in the ceiling. The nozzle element includes an inlet, an outlet, and gas flow passages in fluidic communication with the inlet and outlet for receiving a gas at the inlet and supplying the gas through the outlet into the process chamber. The outlet faces the build area and has a substantially elongate shape that defines a longitudinal direction of the nozzle element. The plurality of gas flow passages subdivide a cavity of the nozzle element at least along the longitudinal direction.

Abstract: A support structure for a three-dimensional object is provided, which support structure and three-dimensional object are produced by means of layer-wise applying and selectively solidifying of a building material. The support structure has a reduced resistance to compressional and/or tensional forces applied to the support structure in a first extension direction of the support structure and in said first extension direction the support structure has an alternating shape including a plurality of crests.