What is 3D printing?

3D printing, also referred to as additive manufacturing, is a method of creating three-dimensional objects using a layering system. Although 3D printing has now been around for many years, the machinery and technology that comes with it are consistently improving. Although these printers utilise a combination of materials including plastic or metal, they are also able to turn digital files created on computer-aided design software into physical objects. 3D printing machines are used throughout many industries including manufacturing, engineering, toolmaking, euro space and the medical profession. Some professions will call this process rapid prototyping, so to find out more on that process, have a read through our blog here.

There are three broad types of 3D printing technologies. 

Sintering 

This method includes where the material is heated, but avoids the point of melting, to create high-resolution products. Metal powder is used for direct metal laser sintering while thermoplastic powders are used for particular laser sintering.

Melting

Utilising powder bed fusion, electron beam melting and direct energy deposition, melting uses lasers, electric arcs or electron beams to print objects. These methods melt the materials together at high temperatures.

Stereolithography 

Uses photopolymerization to create parts. This technology operates the correct light source to interact with the material in a selective manner. This then cures and solidifies a cross-section of the object. 

The 3D printing process involves building up layer upon layer of molten plastic to form a physical object. As each layer sets in place, the next layer is printed on top and the object is built up until the full piece has been created. 

To make a 3D print, a digital file is required that instructs the 3D printer where to print the material. The most common file format for this method is the G-code file which contains ‘coordinates’ to guide the printer’s movements.

3D printers can print these layers at different thicknesses and sizes. Similar to how pixels work, the more layers in a print, the higher the resolution. This then results in a high-quality item. 

3D printing, also known as additive manufacturing, has been categorised into seven process groups. 

Binder Jetting

Binder jetting deposits a thin layer of powdered material such as metal, polymer sand or ceramic, onto the build platform. Drops of adhesive are then deposited by a print head to bind the particles together and build the part layer by layer.

Direct Energy Deposition

Direct energy deposition uses focussed thermal energy such as an electric arc, laser or electron beams to fuse wire or powder feedstock. The process is transited horizontally to create stacked layers. This process can be used with a number of materials, including metals, ceramics and polymers.

Material Extrusion

This method uses a spool of filament which is fed to an extrusion head. The extrusion head then heats, softens and lays down the heated material where it cools to create a layer of material.

Material Jetting

Material jetting works in a similar manner to inkjet printing rather than laying down ink on a page. This procedure deposits layers of liquid from one or more print heads. The layers are then cured before the process begins again.

Powder Bed Fusion

Thermal energy selectively fuses areas of a powder bed to form layers which are built upon each other to create a part. 

Sheet Lamination

Sheet lamination can be split into two different technologies, laminated object manufacturing (LOM) and ultrasonic additive manufacturing (UAM). LOM uses different layers of material to create items with the aesthetic in mind. UAM joins thin sheets of metal via ultrasonic welding. UAM is a low temperature, low energy process that can be used with aluminium, stainless steel and titanium.

VAT Photopolymerization

VAT photopolymerization can be identified into two techniques; stereolithography (SLA) and digital light processing (DLP). These processes both create components layer-by-layer through the use of light to selectively cure the liquid resin in a vat. SLA uses a single-point laser or UV source for the curing process.

3D printing has completely changed the possibilities of how things are conceived, designed, produced and distributed in the manufacturing industry. This advancement has significantly lowered development and production costs, simplified logistics, and lowered company carbon footprints. It also offers modern ways for companies to stay in the competition and create products which are reliable, of high quality and made inefficient production times. 

Some of the benefits which 3D printing brings to manufacturing include: