The revolution of mainstream additive manufacturing.

You can argue that there are many life changing technologies and electronics must be one of these: another is additive manufacturing (3D printing). Whatever you think you know about additive manufacturing, you probably have no idea how important it will become. The technology behind it dates from the 1990s but has come a long way in the last five years. It will speed up as new processes and materials change the way we produce and consume.

As the technology continues to develop, it will impact on business value chains and support new manufacturing processes. It will open new cost-effective ways to produce complex products that are not available or too complex for traditional techniques. For some applications it will also replace traditional techniques such as CNC machining and injection moulding. Additive manufacturing is now moving from prototyping to mainstream production as machining parts from solid metals block is expensive and wasteful. There are also limitations on what is suitable for machining whereas additive manufacturing allows designers new geometries.

As 3D printing technologies have evolved, so too has the name, with the term to additive manufacturing becoming widespread. Depending on who you listen to, there is little or no difference between the two. However, 3D printing has the feeling of home and hobbyist use, whilst manufacturers see additive manufacturing better defines their processes. Both terms relate to the production of parts by building layers of material from a computer CAD file.

Additive manufacturing materials

The processes and materials used for additive manufacturing are developing and this is expanding the number of potential applications. As additive manufacturing gains popularity, new suppliers of everything from feedstock materials to processing equipment technologies are entering the market. From the early plastic deposition models, materials now include titanium alloy; nylon, ABS, aluminium alloys, nickel-based alloys, copper, and even paper and sand.

Sand-like materials include silica sand and ceramics and the printing process uses a polymer to bind the particles together into a physical 3D model. It produces finished products or moulds for pouring materials into, such as foundry applications.

However, new materials bring their own problems that may need standardisation. For example, if you’re machining metals you can specify the exact grade and makeup of the material. When you buy powdered alloys for your powder bed fusion each maker may have their own formulation. This is of importance to manufacturing industries such as automotive and aerospace.

New techniques

A wide range of additive printers is available, covering desktop models for home and lab use to room sized model for industrial processes.  The materials used cover a wide range of metals, plastics, alloys and natural materials.

International standards play an important role in developing the additive manufacturing market. Besides standards for hardware and processes, information technology forms an essential element in  standardisation. To define structure to the industry, there is a move to bring together international organisations from Europe UK (ISO and IEC) and the USA. Their goal is to build classifications for the manufacturing technologies.

The IEC has several technical committees (TCs) working in additive printing from various perspectives such as printer standards or as users of additive manufacturing.  Standards that are foreseen to play an important role in their domains of activities. Loughborough University’s Additive Manufacturing Research Group lists and explains the seven recognised categories for additive manufacturing as being:

Applications

Most early industrial applications were using plastic and nylon parts for rapid prototyping. With the availability of new materials and techniques, additive manufacturing has extended into volume production. Applications cover making production parts for industries from aviation and automotive to consumer and medical parts. In addition to production parts, automotive applications include the development of jigs and fixtures saving both time and cost of production.

The materials and methods selected to produce a part will depend on its purpose and the properties needed. Size is also no longer a problem, with reports of a six-foot long titanium impeller screw or an eight-metre patrol boat made in 72 hours.  Currently there are printers that extrude materials at 70kg an hour with dimensions up to 30ms long x 7m wide and 3m high.

Future

It is almost true that if you can imagine it and make a computer model, then additive printing will enable you to make it. Ideas include printed electronics and footwear, and there may soon come a time that rather than stocking spare parts, you make them as required.

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