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EP-4741085-A1 - INFORMATION PROCESSING APPARATUS, DEFECT DETECTION METHOD, AND THREE-DIMENSIONAL POWDER BED FUSION ADDITIVE MANUFACTURING APPARATUS

EP4741085A1EP 4741085 A1EP4741085 A1EP 4741085A1EP-4741085-A1

Abstract

An information processing apparatus includes a defect detection area setting unit (72) configured to set, on the basis of information input from an input unit (60), an area inside a predetermined amount from a surface of a formed object manufactured by a three-dimensional powder bed fusion additive manufacturing (PBF-AM) apparatus (1) as a defect detection area, and a defect detection unit (74) configured to detect a defect present in the formed object on the basis of layer data obtained for each layer in which the formed object is powder-bed-fusion additively manufactured, to identify a defect detected in the defect detection area as a defect leading to a quality defect, and to output defect information on the identified defect.

Inventors

  • TSUTAGAWA, NARI
  • KANEKO, YUHEI
  • ASANUMA, YUJI
  • TSUDA, TAKASHI
  • Suwa, Kento
  • Ohara, Shuma
  • SHIBATA, KOHEI

Assignees

  • Jeol Ltd.

Dates

Publication Date
20260513
Application Date
20251112

Claims (10)

  1. An information processing apparatus comprising: a defect detection area setting unit (72) configured to set, on the basis of information input from an input unit (60), an area inside a predetermined amount from a surface of a formed object manufactured by a three-dimensional powder bed fusion additive manufacturing (PBF-AM) apparatus (1) as a defect detection area; and a defect detection unit (74) configured to detect a defect present in the formed object on the basis of layer data obtained for each layer in which the formed object is powder-bed-fusion additively manufactured, to identify a defect detected in the defect detection area as a defect leading to a quality defect, and to output defect information on the identified defect.
  2. The information processing apparatus according to claim 1, further comprising a display control unit (75) configured to cause a display unit (90) to display a defect detection area setting screen (Sc1) for setting the defect detection area, wherein the defect detection area setting screen (Sc1) includes a first setting section (St11) for setting the predetermined amount when a boundary between the formed object and a powder bed in an XY cross section of the formed object is set as a starting point.
  3. The information processing apparatus according to claim 2, wherein the defect detection area setting screen (Sc1) includes a defect detection exclusion area setting section (St12) for setting a defect detection exclusion area that is an area where the defect detection unit (74) does not identify a defect leading to a quality defect.
  4. The information processing apparatus according to claim 3, wherein the defect detection exclusion area setting section (St12) includes a second setting section (St14) for setting the predetermined amount when a down skin of the formed object is set as a starting point and/or the predetermined amount when an up skin of the formed object is set as a starting point.
  5. The information processing apparatus according to claim 4, wherein the second setting section (St14) receives an input of the number of layers, which is the number of layers to be laminated in the PBF-AM, as the predetermined amount.
  6. The information processing apparatus according to claim 4, wherein the defect detection area setting screen (Sc1) includes a setting information display section (St3) for displaying the defect detection area and the defect detection exclusion area in a diagram, and the display control unit (75) changes sizes of the defect detection area and the defect detection exclusion area displayed on the setting information display section (St3) in conjunction with sizes of predetermined amounts input to the first setting section (St11) and the second setting section (St14).
  7. The information processing apparatus according to any one of claims 1 to 6, further comprising a forming control unit (71) configured to stop the PBF-AM operation when the defect detection unit (74) identifies a defect leading to a quality defect, wherein, when the defect is detected by the defect detection unit (74) in the defect detection exclusion area, the forming control unit (71) continues the manufacturing operation by the three-dimensional PBF-AM apparatus (1).
  8. The information processing apparatus according to claim 7, further comprising a defect candidate identification unit (73) configured to detect a defective portion generated in the layer as a defect candidate for each layer on the basis of the layer data and to identify a plurality of defect candidates at substantially the same positions in a plurality of layers adjacent in a lamination direction, wherein the defect detection unit (73) detects the defect on the basis of sizes in the lamination direction and sizes in the layers of the plurality of defect candidates located at the substantially same positions identified in the plurality of layers.
  9. A defect detection method performed by a defect detection area setting unit (72) and a defect detection unit (74) included in an information processing apparatus, the method comprising: setting, by the defect detection area setting unit (72), as a defect detection area, an area inside a predetermined amount from a surface of a formed object manufactured by a three-dimensional PBF-AM apparatus (1) on the basis of information input from an input unit (60); and detecting, by the defect detection unit (74), a defect present in the formed object on the basis of layer data obtained for each layer in which the formed object is powder-bed-fusion additively manufactured, identifying a defect detected in the defect detection area as a defect leading to a quality defect, and outputting defect information on the identified defect.
  10. A three-dimensional PBF-AM apparatus comprising: a build plate (22) on which a powder bed is formed, the powder bed being spread with a powder material; a powder supply system (16) configured to spread the powder material on the powder bed; a beam radiation unit (2) configured to radiate forming beam to the powder material spread on the powder bed; an electron optical system configured to scan the forming beam according to melting conditions for melting the powder material to melt the powder material spread on the powder bed; a defect detection area setting unit (72) configured to set, on the basis of information input from an input unit (60), an area inside a predetermined amount from a surface of a formed object manufactured by a three-dimensional PBF-AM apparatus (1) as a defect detection area; a defect detection unit (74) configured to detect a defect present in the formed object on the basis of layer data obtained for each layer in which the formed object is powder-bed-fusion additively manufactured, to identify a defect detected in the defect detection area as a defect leading to a quality defect, and to output defect information on the identified defect.

Description

BACKGROUND Technical Field The present invention relates to an information processing apparatus, a defect detection method, and a three-dimensional powder bed fusion additive manufacturing (PBF-AM) apparatus. Related Art In recent years, a three-dimensional powder bed fusion additive manufacturing (PBF-AM) technique in which layers obtained by thinly laying a powder material of metal are layered one by one is in the limelight, and many types of three-dimensional PBF-AM techniques have been developed depending on the material of the powder material and the manufacturing method. In a building method of a conventional three-dimensional PBF-AM apparatus, for example, a powder material is spread one by one on a base plate installed on the upper surface of a stage. Next, for the powder material spread on the base plate, only a two-dimensional structure portion corresponding to one cross section of a formed object is melted using a heating mechanism including an electron beam or a laser. Then, such layers of powder material are stacked one by one in the height direction (Z direction) to form the formed object. At the time of building each layer of the formed object, a powder bed is formed on the base plate, and thus this building method is also referred to as a powder bed method. In the formation of a formed object, a powder material cannot be completely melted at the portion where a sintering defect occurs, and unevenness occurs on the surface of the formed object in the middle of forming. Since such unevenness may be defects, in the three-dimensional PBF-AM apparatus, defect detection is performed on the basis of data acquired from the surface of the formed object by performing camera imaging or back scattered electron (BSE) imaging. Camera imaging is, for example, a method of imaging the surface of a formed object using visible light. BSE imaging is a method of imaging the surface of a formed object by detecting backscattered electrons of the electron beam radiated to the surface of the formed object. Layer data obtained by camera imaging or BSE imaging is displayed on a monitor as an XY cross-sectional view per layer of the formed object in the middle of forming. A user can check the state of the XY cross section immediately after melting of the powder material using the layer data. Furthermore, the user has been able to identify a portion (referred to as a defect candidate) that may become a defect on the basis of the unevenness of the surface of the formed object in the middle of forming. Examples of a defect candidate include an uneven portion generated in a layer, a portion insufficiently melted and formed with a space. As a technique related to such defect detection, a technique disclosed in Patent Literature 1 is known. Patent Literature 1 discloses that "the determination unit calculates at least one of the height of a convex portion, the total area of the region where the convex portion is generated, and the occupation ratio of the convex portion in a sintered region from the state of the convex portion measured by a surface state measurement unit, and compares the calculated value with a corresponding threshold to determine whether the formation state of a sintered layer is good or poor". Citation List Patent Literature Patent Literature 1: Japanese Laid-open Patent Publication No. 2020-200501 SUMMARY However, the metal powder is not uniformly melted in any area, and there are areas that are hardly melted cleanly. For example, it is confirmed that an area of several layers immediately above the metal powder is hardly melted cleanly, and defects are likely to occur in this area. In addition, it may be difficult to clearly determine the boundary portion between the powder bed and the formed object through BSE imaging, and in this boundary portion, a portion that is not a defect may be erroneously determined as a defect. Furthermore, when the surface roughness of the formed object is high, unevenness similar to that in the case where a defect occurs may occur on the surface, and this unevenness may be erroneously determined as a defect. In addition, it is rare that formed objects manufactured by the three-dimensional PBF-AM apparatus are used as products as they are. For example, in the three-dimensional PBF-AM apparatus, a formed object having a large shape is manufactured, and the surface of the formed object is polished or additionally processed to finish the object into a final product. In a product created in this way, an area called a down skin of several layers from immediately above metal powder and an area called an up skin of an upper layer as described above become a cutting allowance in polishing or additional processing. Therefore, even if a defect occurs in an area serving as a cutting allowance, the defect is irrelevant to the finish of the final product. In a case where there is such an area where erroneous detection of a defect is likely to occur, an area serving as a cutting allowance,