You Guide to 3D Printers:
7 Types of Technologies and Which One is Best for You
- October 4, 2019
- Posted by: Jiamin Ng
- Category: Analytical Instrument IS, BLOG, Industrial Solution
Want to purchase a 3D printer but not sure which one to select? Want to know more about the various 3D printing technologies, and what is the latest innovation in the market?
3D printing, also known as additive manufacturing, is a process whereby three-dimensional solid objects are created from a digital file. Here are seven technologies that you need to know about 3D printing, and what is good and bad about each of them!
1. Material Extrusion
In material extrusion, the first 3D printing technology we are going to introduce, a filament of solid thermoplastic material is pushed through a heated nozzle for melting, then deposited on a build platform along a predetermined path, where it cools and solidifies to form a solid.
Fused Deposition Modelling (FDM)
In FDM 3D printers, a common material extrusion process in many inexpensive, domestic and hobby 3D printers, the material is drawn through a nozzle, heated and deposited layer by layer.
PROS of Material Intrusion
Common and low cost process
ABS plastic usable – good structural properties and easily accessible
CONS of Material Intrusion
Final quality is reduced and limited by nozzle radius
Low speed and accuracy due to limited thickness of the material nozzle
Requires constant pressure of material to increase quality of end product
2. Vat Polymerisation
In vat polymerisation, a vat of liquid photopolymer resin is used where the model is built layer by layer and ultraviolet (UV) light is used to cure or harden the resin.
Under SLA 3D printers, polymers are formed by creating models, prototypes, patterns, and production parts in a layer by layer fashion using photochemical processes by which light causes chemical monomers to link together.
Digital Light Processing (DLP)
A 3D printing process that works with photopolymers, using a more conventional light source applied to the entire surface of the vat of photopolymer resin in a single pass, generally making it faster.
PROS of Vat Polymerisation
High level of accuracy and quality finish
Relatively quick process
Typically for large build areas
CONS of Vat Polymerisation
Longer post processing time and removal from resin
Limited material usage of photo-resins
Requires support structures and post curing for parts to be substantially strong for structural use
3. Powder Bed Fusion (Polymers)
Powder bed fusion (PBF) uses a heat source (eg, laser, thermal print head) to consolidate materials in the form of powder to form 3D objects.
Selective Laser Sintering (SLS)
This is a 3D printing technique that uses laser to sinter powdered material (typically nylon or polyamide), automatically aiming the laser at points in space defined by a 3D model, binding the material together to form a solid.
Multi Jet Fusion (MJF)
IN MJF 3D printers, materials used are thermoplastic polymers (usually Nylon) that come in a granular form. An ink is dispensed on the powder that promotes the absorption of infrared light. An infrared energy source then passes over the building platform and fuses the inked areas.
4. Powder Bed Fusion (Metals)
This is a 3D printing process whereby complex geometries are created by melting layers of powdered metal with a laser or electron beam.
Direct Metal Laser Sintering (DMLS)
A 3D printing technology that uses lasers to fuse powdered metals into functional prototypes and end-use parts.
Electron Beam Melting (EBM)
A fast prototyping or 3D printing technique designed to use a high power-density laser to melt and fuse metallic powders together.
Selective Laser Melting (SLM)
A 3D printing technology that uses fuses metal powder using an electron beam to build parts.
PROS of Powder Bed Fusion
Suitable for visual models and prototypes
Ability to integrate technology into small scale, office sized machine
Powder acts as an integrated support structure
Large range of material options
CONS of Powder Bed Fusion
Relatively slow speed
Lack of structural properties in materials
High power usage
Finish is dependent on powder grain size
5. Material Jetting
One of the fastest and most accurate 3D printing technologies. It builds parts layer upon layer using liquid photopolymer droplets, which are cured and made solid with UV light.
Drop on Demand (DOD)
A 3D printing technology that uses a pair of ink jets to deposit the build materials and add the soluble support material. It follows the path in a point-wise deposition, creating the cross-sectional area of an object layer-by-layer.
PROS of Material Jetting
High accuracy of deposition of droplets hence low waste
Multiple material parts and colours under one process
CONS of Material Jetting
Support material is often required
Materials are limited and only polymers and waxes can be used
6. Binder Jetting
In this 3D printing technology, a binder is selectively deposited onto the powder bed, bonding these areas together to form a solid part layer by layer. Commonly used materials are metals, sand, and ceramics in a granular form.
PROS of Binder Jetting
Parts can be made with a range of different colours
Uses a wide range of materials from metal, polymers and ceramics
The process is generally faster
Large number of different binder-powder combinations and various mechanical properties
CONS of Binder Jetting
Not always suitable for structural parts, due to the use of binder material
Extra post-processing lengthens the overall process
7. ARBURG Plastic Freeforming (APF)
With the ARBURG Plastic Freeforming (APF) 3D printing technology, you can tap into a whole new range of options for industrial additive manufacturing. Currently the newest 3D printing technology in the market, ARBURG’s open freeformer system can produce functional parts using qualified standard granulates via a layer-by-layer application of tiny plastic droplets. A key feature of the open freeformer system is that the same qualified standard granulates as used for injection moulding can be used. This means you can efficiently produce individual parts and small batches from original materials, but also individualise mass-produced items.
PROS of APF
Open-source, able to use any plastic or polymer material of your choice
Save cost by using inexpensive materials instead of being restricted to limited and expensive materials
Flexibility in terms of special support materials for unusual or complex 3D geometries
Able to print functional parts from original materials
CONS of APF
Only for small batch production, unable to cater to massive batch production
Only available for plastics and polymers
Loughborough University. (2019) The 7 Categories of Additive Manufacturing. Retrieved from: https://www.lboro.ac.uk/research/amrg/about/the7categoriesofadditivemanufacturing/