Despite the fact that the terms are often used interchangeably, these two production fields have significant differences in history, application and technology. Let us take a moment to clear them up.
The history of 3D printing (3DP) began at the beginning of this century with the first commercially available 3D printers. These systems are consumer products which can be used as a desktop application in private homes. The price-performance ratio has significantly improved in recent years and the number of different models on the market has increased exponentially. The cost for a single unit is between a few hundred to a few thousand dollars. Makerbot, Lulzbot, Ultimaker, and Printrbot are some of the popular brands in the consumer space today.
The history of Additive Manufacturing (AM) on the other hand, began in the 1980s, when Chuck Hull developed the technology of Stereo Lithography Apparatus (SLA) and Carl Deckard developed the technology of Selective Laser Sintering (SLS) at the University of Texas in Austin. Chuck Hull founded 3D Systems and Charles Deckard founded the Desk Top Manufacturing Corporation (DTM) after their inventions, to make this technology commercially available. Today, U.S. based 3D Systems and Stratasys are the most significant manufacturers in the laser based AM B2B market
Typical 3DP System
Typical AM System
3DP is prevalent in the Business to Consumer (B2C) market and is used by a range of groups: from hobbyists, to tech enthusiasts, to the DIY’s and makers that need specialized, small batch production.
AM systems however, are professional industrial grade systems which are sold in the Business to Business (B2B) market. Size and accuracy of these systems are significantly higher and the price for a single unit is typically several hundred-thousand dollars.
In 3DP, the most frequently used materials are thermoplastic polymers like ABS and PLA plastics because they can be melted and extruded through a nozzle. This technology is called Fused Deposition Modelling (FDM). Another frequently used 3DP technology is 3D Printing (notice the capital P) which continuously dispenses a polymer-powder and glue mixture. After dispensing, the glue cures to act as a binding agent, enabling a solid structure to form. Recently, 3D printers using this technology have also been developed to bind metal powder.
In AM, there are two technologies at play – SLA and SLS. In the SLA technology, a polymer resin is cured using laser energy. In SLS, materials such as polymers, metals, polymer-polymer blends, or metal-metal powder blends, are sintered using laser energy. During SLA, the laser energy is used to initiate a chemical process of irreversibly linking the polymer resin and curing it while in SLS the heat energy of the laser is used to either melt the powder completely or sinter the power particles together. Sintering means that individual power particles are molten at the contact surface and thus connected after solidification. Most notably, the laser based AM system enable the processing of metal, ceramic and carbide power.
Benefits provided by 3D production technologies
Both technologies have enabled innovations in several different industries and are considered as one of the key factors of the currently proceeding industrial revolution, also referred to as 4th industrial revolution or Industry 4.0 (the other factors are intelligent robotics and communicating electronics). In the fields of aerospace and automobile, AM increased functionality and efficiency of products and production.
Although new geometries are possible, the utility of AM mainly regards improvements of the already existing manufacturing techniques. In the fields of medicine and biotechnology AM enables procedures which were previously contrived but not effectively feasible. In medicine, AM enables the production of models of individual body parts - enabling the simulation of surgeries. In biotechnology, it aids in the printing of cellular parts as an alternative to growing them in vitro.