3D printing, also known as additive manufacturing, is the computer-controlled sequential layering of materials to create three‑dimensional shapes. Originally developed more than 30 years ago, it is only in recent years that applications of the technology have expanded in fields as diverse as aerospace, medicine and dentistry, construction, the automotive industry and clothing and footwear.
The main 3D printing technologies include Fused Deposition Modelling (FDM: melting of thermoplastic material by heating and then extruding it to create an object layer by layer), Selective Laser Sintering (SLS: using a high power carbon dioxide laser to fuse small particles of metal or plastic powder into 3D objects), Electron Beam Melting (EBM: using a cathode ray as a heat source to melt metal powder in a high vacuum, layer by layer, to create a product) and Stereolithography (SLA: producing 3D models layer by layer by curing a photo-reactive resin with a UV laser).
The additive nature of 3D printing helps in reducing wastage of materials and the associated costs. It now has a growing range of uses beyond rapid prototyping. Although 3D printers are still not cost-effective for most high-volume commercial manufacturing, they are faster and easier to use than they were, and can handle multiple materials. The expiry of key patents has allowed many small companies to produce cheap desktop 3D printers aimed at consumers.
A number of IEC Technical Committees (TCs) and Subcommittees (SCs) develop and coordinate International Standards covering the safety aspects of 3D printing and the electric and electronic components and technology used in additive manufacturing equipment.
Research is now under way on the next stage, dubbed “4D printing”, which involves the use of 3D-printed objects and materials able to change shape over time when immersed in liquids or exposed to external energy sources.
Shape shifting and the fourth dimension
The next few years will see rapid advances in metal 3D printing to produce a wider range of finished goods, including more medical implants than is possible today. The speed of printers is expected to increase. Research is underway on how to combine different types of materials such as metals and plastics in a single build cycle, and how to embed components such as sensors, electronics and batteries.
The emerging technology of 4D printing brings exciting possibilities. 4D printing involves the use of shape-shifting materials, where the fourth dimension relates to the time taken for self‑transformation. These programmable or ‘smart’ materials can adapt their properties and shape on demand after 3D printing, when immersed in water or exposed to external sources of energy such as heat, current or light. Potential applications include tissue engineering and medical implants that change their shape inside the body.
Read full tech article by Peter Feuilherade here.