Method and apparatus for additive manufacture of a workpiece

An apparatus for additively manufacturing a workpiece, the apparatus comprising:

• a memory configured to store a dataset that defines the workpiece in a plurality of workpiece layers arranged one on top of the other;
• a manufacturing platform;
• a layer forming tool;
• a heating tool;
• a camera directed at the manufacturing platform;
• and
• an evaluation and control unit configured to:
• produce a plurality of workpiece layers arranged one on top of the other on the manufacturing platform using the layer forming tool and the dataset, the plurality of workpiece layers forming a layer stack which, at a defined instant of time, has a topmost workpiece layer and a number of workpiece layers underneath,
• thermally excite the layer stack at the defined instant of time using the heating tool,
• record a sequence of images of the topmost workpiece layer using the camera,
• determine an individual temporal deformation profile of the topmost workpiece layer in response to the thermal excitation using the sequence of images, and
• inspect the layer stack using the individual temporal deformation profile,
• wherein the individual temporal deformation profile has a plurality of characteristic features including an individual deformation increase, an individual deformation maximum, and an individual deformation decrease, and
• wherein the evaluation and control unit determines an inspection result using at least one of the characteristic features from the plurality of characteristic features.