530
M. Matsumoto et al.
• Post machining planning
Post machining is required after 3D printing the damaged part to achieve the desirable
dimensional tolerance, hardness and surface roughness and to ensure like-new performance. There are techniques to minimize the surface roughness, for example, through
optimizing building paths, layer thickness, and powder grain size (Matsumoto et al.
2016). However, a better surface from the 3D printing process usually means a more
expensive and time-consuming process. This is where post-processing comes in.
Post-processing is usually a material-removing process such as cutting and abrasive
processes like polishing. There exists the optimization of the combination of AM
and subtractive manufacturing, but they are mainly for new product manufacturing
and not designed for remanufacturing (Matsumoto et al. 2016). The challenge on this
respect is to develop a sound method to combine metal 3D printing and subtractive
manufacturing in an optimal way.
• Post-inspection and in-situ monitoring
In metal 3D printing, defects and variation in quality may arise in each product as
it is fabricated through layer-by-layer deposition of materials; thus, post-inspection
is important. An X-ray computerized tomography scan technique can be used to
inspect the fabricated product; however, it is expensive and comes with a problem,
wherein detection becomes difficult as the defect size becomes smaller. This issue
can be resolved via development of highly precise and low-cost quality inspection
techniques and establishment of an appropriate inspection standard. In addition, if
the defect occurrence during the process can be detected and further reflected in the
process parameters immediately, the quality of restoration can improve significantly.
Development of such in-situ monitoring technique is also a challenge.
• Cost reduction of the process
Cost reduction of the process is important to expand the use of metal 3D printing
in remanufacturing. Here, price reduction of the device is a challenge. The high
price of powder materials today is another hindrance factor for the expansion of the
applications; thus, reducing the powder cost is also a challenge.
36.5 Conclusion
The study presented a survey of existing industrial usage of conventional AM in
remanufacturing and a review of R&D of metal 3D printing applications in remanufacturing. Conventional AM is widely used in remanufacturing, of which cladding
by welding and re-coating are the most popular. Further promoting the usage of
conventional AM in circular manufacturing essentially incorporates cost reduction
and quality enhancement of AM, and associates with the challenges of advancing
M. Matsumoto et al.
• Post machining planning
Post machining is required after 3D printing the damaged part to achieve the desirable
dimensional tolerance, hardness and surface roughness and to ensure like-new performance. There are techniques to minimize the surface roughness, for example, through
optimizing building paths, layer thickness, and powder grain size (Matsumoto et al.
2016). However, a better surface from the 3D printing process usually means a more
expensive and time-consuming process. This is where post-processing comes in.
Post-processing is usually a material-removing process such as cutting and abrasive
processes like polishing. There exists the optimization of the combination of AM
and subtractive manufacturing, but they are mainly for new product manufacturing
and not designed for remanufacturing (Matsumoto et al. 2016). The challenge on this
respect is to develop a sound method to combine metal 3D printing and subtractive
manufacturing in an optimal way.
• Post-inspection and in-situ monitoring
In metal 3D printing, defects and variation in quality may arise in each product as
it is fabricated through layer-by-layer deposition of materials; thus, post-inspection
is important. An X-ray computerized tomography scan technique can be used to
inspect the fabricated product; however, it is expensive and comes with a problem,
wherein detection becomes difficult as the defect size becomes smaller. This issue
can be resolved via development of highly precise and low-cost quality inspection
techniques and establishment of an appropriate inspection standard. In addition, if
the defect occurrence during the process can be detected and further reflected in the
process parameters immediately, the quality of restoration can improve significantly.
Development of such in-situ monitoring technique is also a challenge.
• Cost reduction of the process
Cost reduction of the process is important to expand the use of metal 3D printing
in remanufacturing. Here, price reduction of the device is a challenge. The high
price of powder materials today is another hindrance factor for the expansion of the
applications; thus, reducing the powder cost is also a challenge.
36.5 Conclusion
The study presented a survey of existing industrial usage of conventional AM in
remanufacturing and a review of R&D of metal 3D printing applications in remanufacturing. Conventional AM is widely used in remanufacturing, of which cladding
by welding and re-coating are the most popular. Further promoting the usage of
conventional AM in circular manufacturing essentially incorporates cost reduction
and quality enhancement of AM, and associates with the challenges of advancing