Method for additive manufacturing

A program element configured and arranged when executed on a computer to implement a method for forming at least one three-dimensional article through successive fusion of parts of a powder bed, which parts correspond to successive cross sections of the at least one three-dimensional article, said method comprising the steps of:

• providing a model of said at least one three dimensional article;
• applying a first powder layer on a work table;
• directing at least one energy beam over said work table causing said first powder layer to fuse in selected locations according to said model to form a first cross section of said three-dimensional article;
• applying a second powder layer on said work table;
• directing the at least one energy beam over said work table causing said second powder layer to fuse in selected locations according to said model to form a second cross section of said three-dimensional article, wherein said second layer is bonded to said first layer;
• detecting a local thickness in at least two positions in at least said second powder layer;
• and
• varying an energy beam parameter depending on the detected local thickness of said second powder layer in order to melt said second powder layer and to remelt at least a predetermined thickness of said first cross section.

A non-transitory computer program product comprising at least one non-transitory computer-readable storage medium having computer-readable program code portions embodied therein, the computer-readable program code portions comprising:

• an executable portion configured for, upon receipt of a model of at least one three dimensional article, applying a first powder layer on a work table so as to initiate forming said at least at least one three-dimensional article through successive fusion of parts of a powder bed, which parts correspond to successive cross sections of the at least one three-dimensional article;
• an executable portion configured for directing at least one energy beam over said work table causing said first powder layer to fuse in selected locations according to said model to form a first cross section of said three-dimensional article;
• an executable portion configured for applying a second powder layer on said work table;
• an executable portion configured for directing the at least one energy beam over said work table causing said second powder layer to fuse in selected locations according to said model to form a second cross section of said three-dimensional article, wherein said second layer is bonded to said first layer;
• an executable portion configured for detecting a local thickness in at least two positions in at least said second powder layer;
• and
• an executable portion configured for varying an energy beam parameter depending on the detected local thickness of said second powder layer in order to melt said second powder layer and to remelt at least a predetermined thickness of said first cross section.