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Remanufacturing and Advanced Machining
More specifically, the generic AM process can be described in eight steps (Gibson
et al., 2021):
Step 1: CAD. A software model fully describes the external geometry. This
can involve the use of almost any professional CAD solid modeling software, but the output must be a 3D solid or surface representation. Reverse
engineering (e.g., laser and optical scanning) equipment can also be used to
create this representation.
Step 2: Conversion to STL. The STL file format has become a de facto standard accepted by all AM machines, and nowadays nearly every CAD system can output such a file format. This file describes the external closed
surfaces of the original CAD model and forms the basis for calculation of
the slices.
Step 3: Transfer to AM machine and STL file manipulation. In the AM
machine, there may be some general manipulation of the file to put it in the
correct size, position, and orientation for building.
Step 4: Machine setup prior to the build process. Such settings would relate to
the build parameters, such as the energy source, material constraints, layer
thickness, timings, etc.
Step 5: Building the part, which is mainly an automated process performed
without supervision. Only superficial monitoring of the machine needs to
take place.
Step 6: Removal of the completed product. This may require interaction with
the machine, which may have safety interlocks.
Step 7: Post-processing of the part removed from the machine, e.g., additional
cleaning or removal of supporting features. The parts may require priming
and painting to obtain a desirable surface texture and finish, or heat treatment to enhance their properties. Post-processing may be costly, laborious,
and lengthy if finishing requirements are very demanding.
Step 8: Application of the parts ready for use. This may require them to be
assembled together with other mechanical or electronic components to
form a final product.
Additive manufacturing has important capabilities such as creating shape complexity, hierarchical complexity, material complexity, and functional complexity, so
that plastic prototypes, complex engine components, houses, food, and even human
organs can now be 3D printed (Wang et al., 2017). Kumar and Sathiya (2021) point
out many distinctive features attainable by AM techniques, impossible for conventional manufacturing processes. First of all, AM processes are able to fabricate
internal geometries of functional components and highly complex parts as a single
object eliminating assembled features produced by traditional manufacturing processes, thus eliminating structural joint failures over time. In addition, direct fabrication is possible with AM processes, which involves no tooling and manufacturing
sequences. Moreover, it can use functionally gradient materials and varying material compositions to produce multifunctionality features with higher mechanical
Remanufacturing and Advanced Machining
More specifically, the generic AM process can be described in eight steps (Gibson
et al., 2021):
Step 1: CAD. A software model fully describes the external geometry. This
can involve the use of almost any professional CAD solid modeling software, but the output must be a 3D solid or surface representation. Reverse
engineering (e.g., laser and optical scanning) equipment can also be used to
create this representation.
Step 2: Conversion to STL. The STL file format has become a de facto standard accepted by all AM machines, and nowadays nearly every CAD system can output such a file format. This file describes the external closed
surfaces of the original CAD model and forms the basis for calculation of
the slices.
Step 3: Transfer to AM machine and STL file manipulation. In the AM
machine, there may be some general manipulation of the file to put it in the
correct size, position, and orientation for building.
Step 4: Machine setup prior to the build process. Such settings would relate to
the build parameters, such as the energy source, material constraints, layer
thickness, timings, etc.
Step 5: Building the part, which is mainly an automated process performed
without supervision. Only superficial monitoring of the machine needs to
take place.
Step 6: Removal of the completed product. This may require interaction with
the machine, which may have safety interlocks.
Step 7: Post-processing of the part removed from the machine, e.g., additional
cleaning or removal of supporting features. The parts may require priming
and painting to obtain a desirable surface texture and finish, or heat treatment to enhance their properties. Post-processing may be costly, laborious,
and lengthy if finishing requirements are very demanding.
Step 8: Application of the parts ready for use. This may require them to be
assembled together with other mechanical or electronic components to
form a final product.
Additive manufacturing has important capabilities such as creating shape complexity, hierarchical complexity, material complexity, and functional complexity, so
that plastic prototypes, complex engine components, houses, food, and even human
organs can now be 3D printed (Wang et al., 2017). Kumar and Sathiya (2021) point
out many distinctive features attainable by AM techniques, impossible for conventional manufacturing processes. First of all, AM processes are able to fabricate
internal geometries of functional components and highly complex parts as a single
object eliminating assembled features produced by traditional manufacturing processes, thus eliminating structural joint failures over time. In addition, direct fabrication is possible with AM processes, which involves no tooling and manufacturing
sequences. Moreover, it can use functionally gradient materials and varying material compositions to produce multifunctionality features with higher mechanical