Device and Method for a Layerwise Manufacturing of a Three-Dimensional Object from a Building Material in Powder Form

Abstract

A method is provided, by which a three-dimensional object is manufactured by a subsequent solidification of layers of a building material in powder form at the positions in the respective layer that corresponds to the cross-section of the object by means of the action of a laser or another energy source, wherein as building material in powder form a material is used which contains the old powder that has remained as unsolidified powder in the manufacturing of one or more previously formed objects and a proportion of new powder that has not been used before in any manufacturing process, characterized in that the building material in powder form is mechanically consolidated when a layer is applied.

1 . Device for manufacturing a three-dimensional object by a subsequent solidification of layers of a building material in powder form at those positions in the respective layers corresponding to the cross-section of the object by the action of a laser or another energy source having
 a support, on which the object is built,   an application device for applying layers of a powder material onto the support or a previously solidified layer, wherein the application device is movable in at least one application direction (B) across the support or the previously solidified layer,   a solidification device for solidifying the powder material at those positions in the respective layer that correspond to the object,   characterized in that the application device comprise a blade with an application surface, that rises in the direction of the application, wherein the application surface is provided at the bottom side of the blade facing the support and rises under an angle, which is larger than 0.2° and smaller than approximately 5°, preferably between approximately 0.5° and approximately 3°, further preferably between approximately 0.7° and approximately 2.8° in the direction of movement (B) of the application device.   
   
   
       2 . Device according to  claim 1 , characterized in that the ascending slope of the surface is between approximately 0.01 and approximately 0.06. 
   
   
       3 . Device according to  claim 1 , characterized in that the width of the application surface in the direction of movement lies between approximately 1 mm and approximately 20 mm, preferably at approximately 6 mm. 
   
   
       4 . Device according to  claim 1 , characterized in that the height of the application surface is larger than approximately 0.03 mm and smaller than approximately 0.5 mm, preferably larger than approximately 0.08 mm and smaller than approximately 5 mm. 
   
   
       5 . Device according to  claim 1 , characterized in that the application device has two blades that are arranged at a distance to each other and are formed mirror-symmetrically to a plane that is perpendicular to the direction of movement (B) of the application device. 
   
   
       6 . Device according to  claim 1 , characterized in that the blade is formed symmetrically and has two application surfaces. 
   
   
       7 . Method for manufacturing a three-dimensional object by a subsequent solidification of layers of a building material in powder form at those positions in the respective layer that correspond to the cross-section of the object by the action of a laser or a different energy source, wherein a powder is used that has a solution viscosity which is larger than 2.1 η rel and
 wherein the powder is mechanically consolidated during the application of a layer.   
   
   
       8 . Method for manufacturing a three-dimensional object by a subsequent solidification of layers of a building material in powder form at the positions in the respective layer that correspond to the cross-section of the object by the action of a laser or a different energy source,
 wherein a powder is used, which has a melt viscosity that corresponds to a solution viscosity for PA 2200 that is larger than 2.1 η rel and   wherein the powder is mechanically consolidated during the application of a layer.   
   
   
       9 . Method according to  claim 7 , characterized in that by the consolidation a powder bed density is produced which is larger than 0.38 g/cm 3 . 
   
   
       10 . Method according to  claim 7 , characterized in that a powder bed density is produced which is larger than 0.4 g/cm 3  and preferably larger than 0.41 g/cm 3 , further preferably larger than 0.42. 
   
   
       11 . Method according to  claim 7 , characterized in that the solution viscosity is larger than approximately 2.1, preferably larger than approximately 2.3 and further preferably larger than approximately 2.6 η rel. 
   
   
       12 . Method according to  claim 7 , characterized in that as building material in powder form a material is used, which comprises old powder that has remained as unsolidified powder in the manufacturing of one or several previously formed objects and new powder that has not been used before in any manufacturing process. 
   
   
       13 . Method for manufacturing a three-dimensional object by a subsequent solidification of layers of a building material in powder form at the positions in the respective layer that correspond to the cross-section of the object by the action of a laser or a different energy source,
 wherein as building material in powder form a material is used, which contains the old powder that has remained as unsolidified powder in the manufacturing of one or several previously formed objects and a proportion of new powder that has not been used before in any manufacturing step, characterized in that   the building material in powder form is mechanically consolidated when applying a layer and the proportion of new powder is smaller than 50% of the total amount of powder used for the building process.   
   
   
       14 . Method according to  claim 7 , characterized in that a plastic powder is used as material. 
   
   
       15 . Method according to  claim 14 , characterized in that the material contains a polyamide powder, preferably polyamide 12. 
   
   
       16 . Method according to  claim 7 , characterized in that the method is performed with a device according to  claim 1 . 
   
   
       17 . Method according to  claim 7 , characterized in that the object manufactured by the method does not have any dip positions. 
   
   
       18 . Method according to  claim 12 , characterized in that the object manufactured by the method does not have any dip positions.