Powder bed fusion (PBF) technology is useful for the production of high-value products that are not technically feasible with a traditional method. Melted powder can be solidified and stacked in layers. However, there was a limit to using it at industrial sites because the size of parts that can be manufactured with PBF equipment is only up to 50 centimeters (19.7 inches).
A research team led by Kim Hyun-gil from the Korea Atomic Energy Research Institute (KAERI) has opened the way for the commercialization of PBF technology by developing a 3D printer that can manufacture parts of up to 100 centimeters wide and 50 centimeters long. The institute predicted that the development of a printer capable of manufacturing parts for several meters is possible.
"We hope it will be applied not only to high-tech nuclear technologies but also to the manufacture of large parts in other industries such as energy, environment, defense, and space industries," KAERI head Park Won-seok said in a statement on February 24. Kim's team has cooperated with CSCAM, a company specializing in metal cutting machinery, to manufacture five types of trial products made of nickel alloy materials and a nuclear power plant heat exchanger.
Through technology upgrading, the institute said that researchers would seek the development of reverse design, which scans and manufactures the actual objects of discontinued parts, and the production of core components of ultra-small reactors for space and innovative small modular reactors.
The research team has devised "parallel expansion" technology to eliminate the size constraint of PBF 3D printing by connecting laser sources and scanners side by side. Two laser sources and scanners each were set up to increase the available range to 1.0 m in width.
For high precision, the research team has established variable values for laser speed and pattern by combining experiments and simulation programs. As a result, deformation caused by heat and stress can be predicted in advance to make a smooth connection area without defects.