Introduction to Additive Manufacturing: definition, how it works, applications
What is Additive Manufacturing?
Additive manufacturing is a production process that allows you to create three-dimensional objects by adding material layer by layer until the desired shape is obtained. Unlike traditional subtractive manufacturing methods, such as milling or turning, additive manufacturing builds objects by adding material rather than removing it. We have already explored the differences between additive manufacturing and traditional manufacturing, but in this article we will discuss Additive Manufacturing in more detail.
According to the definition of Additive Manufacturing given by the ISO/ASTM 52900:2021 terminology standard, “it is a process of joining materials to make parts (3.9.1) from 3D model data, usually layer (3.3.7) upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies”
Is 3D printing the same as additive manufacturing?
3D printing is a type of additive manufacturing. Additive manufacturing is a process of creating three-dimensional objects using 3D printing. These two terms are often used interchangeably, therefore, mentioning additive manufacturing or 3D printing will mean referring to the additive approach to distinguish it from subtractive manufacturing processes, such as machining, in which material is removed from a larger block to get the desired shape.
In recent years, the market is increasingly relegating the concept of additive manufacturing to the 3D printing production process by putting it on the same level as traditional methods, as it enables the production not only of prototypes but also of finished parts, associating 3D printing with hobbyist or domestic solutions, called Desktop.
History and timeline of additive manufacturing
Additive manufacturing dates back to the 1980s, when Chuck Hull introduced stereolithography (SLA) technology at 3D Systems. SLA used a laser to solidify layers of light-sensitive resin, allowing for the creation of three-dimensional models. Over the years, several other 3D printing technologies have been developed and commercialized: from selective laser melting (SLM), which uses a laser to melt and solidify metal powders, to fused material deposition (FDM/FFF), which extrudes a layer of melted plastic material to build the object layer by layer.
From the 2000s onwards, additive manufacturing evolved and began to be increasingly used for the additive manufacturing of prototypes in various industrial sectors, such as aerospace and automotive, as it allowed to reduce time and costs of development. Advanced materials, such as high-performance thermoplastic polymers and metal alloys, have been introduced, expanding the possibilities of additive manufacturing.
In recent years we have witnessed a real change of pace, with an unstoppable speed in terms of progress with new 3D printing technologies and new perspectives for innovation in an ever wider range of sectors: from biomedical to space, from construction to naval, from energy to industrial, each with 3D printing processes and materials developed ad hoc based on individual needs. In the future, 3D printing technology is expected to further revolutionize the way things are designed and produced, providing new opportunities for customization, sustainability and efficiency in production.
Additive Manufacturing: how does it work?
The additive manufacturing process begins with the creation of a three-dimensional digital model of the desired object using computer-aided design (CAD) software. This model is then divided into thin layers, usually a few micrometers thick. The most famous file format for 3D printing is the STL (Standard Tessellation Language or alternatively Standard Triangulation Language), introduced in the 90s for the communication of three-dimensional data between design software and 3D printing machines. Once the digital project has been obtained, we move on to the setting phase of the print parameters through a slicing software. Generally, this is a crucial step that could also affect the success and quality of the 3D printed parts. Choosing the printing settings to make a 3D part is essential before starting any job on the machine.
During the 3D printing process, the build material is deposited or melted according to the specifications of the digital model, hardened or solidified, and then the process is repeated for each layer until the object is complete. Once the object is fully printed, it can undergo further finishing, such as removing supports or sanding, to achieve the desired final shape.
Advantages of Additive Manufacturing
As already explained in this article about the advantages of 3D printing, the advantages of using additive manufacturing compared to traditional methods are, in summary:
• Complex geometries: The additive approach allows for greater design freedom than conventional methods. With 3D printing it is possible to obtain objects with complex geometries, impossible to obtain with subtractive technologies. This advantage opens up new opportunities for custom product design.
• Custom production: Additive manufacturing offers the ability to create customized products according to specific customer needs. Thanks to the flexibility of the process, changes to the design can be made quickly and cost-effectively, allowing for the production of smaller batches or even single pieces.
• Reduction of production costs: while the initial costs of industrial 3D printing equipment can be significant, additive manufacturing can offer long-term economic benefits. For example, it can eliminate the need to create expensive tooling to produce small batches of products. Additionally, reducing material waste and production time can help reduce overall costs.
• Reduced production time: With 3D printing it is possible to obtain a significant reduction in production times as the additive method does not need special tools or molds and allows the production of finished parts by reducing assembly times.
• Reduction of material waste: In additive manufacturing, material is deposited only where it is needed, reducing material waste compared to subtractive processes, such as milling or turning. This leads to more efficient use of resources and can reduce costs associated with purchasing and managing materials.
• Digitization of the warehouse: Additive manufacturing enables a new concept of warehouse by transforming it from physical to digital. In a digital warehouse, digital files of the three-dimensional models of the objects are stored, together with additional information such as the printing specifications, the materials used and other characteristics, useful for 3D printing the parts whenever and wherever needed.
Additive Manufacturing applications: some examples
Additive manufacturing is used to produce prototypes, custom parts, tools and much more. It has applications in several industries, including automotive, aerospace, energy, medical, architecture and fashion. The most used additive manufacturing applications are:
• Additive production of functional prototypes: 3D printing allows for the rapid creation of physical prototypes of products, allowing engineers and designers to test and evaluate the design before launching mass production. This reduces the development time and costs associated with producing traditional prototypes.
• Additive manufacturing of custom parts: Additive manufacturing enables the efficient production of customized parts. This technology finds application in areas where the production of parts tailored to specific customer or patient needs is required.
• Additive manufacturing of tools and equipment: the most common. 3D printing is used to produce custom tools, fixtures and devices. For example, it can be used to create specialized tools for machining materials or ad hoc fixtures.
• Additive manufacturing of lightweight and complex components: Additive manufacturing allows to create components with complex geometries that would be difficult or impossible to produce with traditional methods. This technology is used in the automotive, aerospace and mechanical industries to create light, strong and complex parts such as turbines, engine housings and structural components. By combining technology with advanced materials, such as super polymers and composites, we help companies obtain even faster lightweight and optimized parts for the final application.