3D New Age of Manufacturing
By Nicole Leo & Ludwig
Conventional production processes involve removing parts of a larger piece of material to produce the final desired object. This is referred to as subtractive manufacturing. Conversely, additive manufacturing techniques such as revolutionary 3D printing use the reverse logic of production; that is, layers of material are added or combined to create the object.
There are different 3D printing technologies. For instance, binder jetting is a process in which adhesive or binding agent is selectively deposited onto powdered material particles by a print-head, similar to an inkjet printer, to form layer upon layer of solid material, according to the desired shape and size specified by the digital design. Another example called laser powder bed fusion uses laser powder to melt and fuse metallic powders together. 3D printing constitutes a main part of a set of techniques known as rapid prototyping, whereby a scale model is fabricated in short order using computer-aided design.
Initial Stumbling Block
The first 3D additive manufacturing invention was credited to Hideo Kodama of Nagoya Municipal Industrial Research Institute in the 1980s. He was the pioneer of layer-by-layer manufacturing, fabricating 3D plastic models through UV light polymerization.
Proliferation of the technology was difficult due to patents obtained by early inventers, such as the patenting of stereolithography fabrication by Charles Hull (who established 3D Systems Corporation) in 1986. Another stumbling block was the high cost of 3D printing machinery, which deterred the vast majority of manufacturers from committing to adopting this method of production.
While research into 3D printing and rapid prototyping continued, it was only in the late 2000s that these technologies came into the spotlight due to patents expiring and innovative inventions. In 2005, the University of Bath commenced the RepRap project, developing a low-cost 3D printer which was offered to the public. Such achievements propelled progress on existing designs and techniques, advancing 3D printing considerably.
Recently the most popular and widely used form of 3D printing is fused deposition modeling (FDM), which is easier to operate and works with easily obtainable materials such as plastic and rubber. In this process, the object is constructed by depositing melted material layer by layer. Laser- or digital-light 3D processing is more expensive but more precise; it’s commonly utilized in dentistry to print dentures, crowns, bridges, and other custom molds. 3D metal printing mostly involving laser processing to fuse metallic powders is even more expensive and involves larger machinery. However, it is effective at reducing material wastage and increasing production efficiency.
In 2015, doctors at St Thomas’ Hospital in England performed a risky but successful kidney transplant for two-year-old Dexter Clark, supported by 3D-printing technology. Surgeons used 3D-printed anatomical models of Dexter and his father, who was Dexter’s kidney donor, to plan for and evaluate the procedure which was made tricky by the complexities of transplanting an adult kidney into a young child.
The Dutch construction company Van Wijnen launched Project Milestone with the aim of building the world’s first habitable 3D-printed houses. The project cuts costs and environmental impact by reducing cement usage. These small 3D houses are constructed by releasing a special type of cement from a nozzle situated along a large robotic arm of the 3D printer. The cement is printed layer upon layer to form walls, with space allocated for metal fittings to increase stability of the structure. The technique makes it possible to have customizable, flexible designs of different shapes.
Australian company Titomic’s kinetic fusion production method is the first additive manufacturing technology to overcome metal oxidation issues. The inventors achieved this by creating a process that requires 3D printing to be conducted in a vacuum environment. Titomic developed a 3D metal printer that is approximately the size of a bus and can print an aircraft wing as long as nine meters. Their method has sparked the interest of an Italian ship manufacturer and shows the promise of 3D printing for large-size industrial production.
Gartner, a global research and advisory firm, predicts that manufacturers of medical devices, aircrafts and consumer goods will further embrace 3D printing.
The prominence of 3D manufacturing will likely bring about an era of low-waste, high-speed and high-customization production. Perhaps in the near future, we will be able to print even simple daily products ourselves.