3D printing

·       3D printing or additive manufacturing is a process of making three dimensional solid objects from a digital file.

·       The creation of a 3D printed object is achieved using additive processes. In an additive process an object is created by laying down successive layers of material until the object is created. Each of these layers can be seen as a thinly sliced cross-section of the object.

·       3D printing is the opposite of subtractive manufacturing which is cutting out / hollowing out a piece of metal or plastic with for instance a milling machine.

·       3D printing enables you to produce complex shapes using less material than traditional manufacturing methods.

·       The USA is the global leader in 3D printing, with more than 35% market share. In Asia, about 50% of its market is cornered by China, followed by Japan at 30%, and South Korea at 10%.

Applications of 3D Printing

·       Defence and Aerospace: At present, 3D printing technology in the aerospace and defence sector is broadly used for prototyping, repair of small parts and component manufacturing.

·       Health: Hearing aids have been made using 3D printing technology.

·       Bio printers: Organ printing or body part printing is being printed and some parts being used as implants of actual body parts. Example: Titanium pelvic, plastic tracheal splint, titanium jaws. Tissue engineering made remarkable progress with printing of 3D blood vessels. 3D printing is being used to make surrogate body parts

·       Manufacturing: 3D printing can be used to manufacture varied forms of products- from car or plane parts to sport goods, toys etc.

·       Architecture & housing: The technology can be used for a variety of housing projects. It could also enable engineers to design and build stiffer and safer geometries for houses. Further, can also help engineers to rebuild and restore old heritage designs quickly yet accurately.

·       Food: 3D printing enables fast automated and repeatable processes, freedom in design, as well as allowing large and easy variability of the cooking process which can be customized.

Advantages of 3D printing 

·       This technology allows for the easy creation of bespoke geometric parts where added complexity comes at no extra cost. In some instances, 3D printing is cheaper than subtractive production methods as no extra material is used.

·       Since no moulds are required, the costs associated with this manufacturing process are relatively low. The cost of a part is directly related to the amount of material used, the time taken to build the part and any post processing that may be required.

·       Because the process is based upon computer aided designs (CAD), any product alterations are easy to make without impacting the manufacturing cost.

·       Because the technology allows for small batches and in-house production, this process is ideal for prototyping, which means that products can be created faster than with more traditional manufacturing techniques.

·       Although plastics and metals are the most common materials used in 3D printing, there is also scope for creating parts from specially tailored materials with desired properties. So, for example, parts can be created with high heat resistance, water repellency or higher strengths for specific applications.

Disadvantages of 3D printing 

·       While some parts, such as those made from metal, have excellent mechanical properties, many other 3D printed parts are more brittle than those created by traditional manufacturing techniques. This is because the parts are built up layer-by-layer, which reduces the strength by between 10 and 50%.

·       Large production runs are more expensive with 3D printing as economies of scale do not impact this process as they do with other traditional methods. Estimates suggest that when making a direct comparison for identical parts, 3D printing is less cost effective than CNC machining or injection moulding in excess of 100 units, provided the parts can be manufactured by conventional means.

·       The accuracy of a printed part depends on the type of machine and/or process used. Some desktop printers have lower tolerances than other printers, meaning that the final parts may slightly differ from the designs. While this can be fixed with post-processing, it must be considered that 3D printed parts may not always be exact.

·       Most 3D printed parts require some form of post-processing. This may be sanding or smoothing to create a required finish, the removal of support struts which allow the materials to be built up into the designated shape, heat treatment to achieve specific material properties or final machining.