Additive manufacturing: an overview for modern manufacturers

The word “manufacturing” suggests a process of building something up, of connecting components, going from many small items to a single finished object. But often, that’s not quite true.

Traditional manufacturing methods often involve removing unwanted material. It employs processes of shaping an object by removing pieces of material so that it eventually takes the form you want. We call this subtractive manufacturing.

The material removed is a byproduct which goes by various names. In a CNC milling machine or lathe, it’s called swarf. It’s offcuts, shavings and chips by another name. Whatever you call it, it’s waste material and it can be seen as an indicator of an inefficient process.

What makes additive manufacturing so exciting is that it doesn’t create swarf. Instead of subtracting, we’re adding and that brings with it a great many benefits.

What is additive manufacturing?

Additive manufacturing is a production technique that creates objects by depositing and fusing material sequentially in layers, rather than removing material like in traditional subtractive methods. Designers can create an object as a CAD model and the 3D printer will simply “print” the design. This process can be completed in various different materials, from plastic composites to metals and ceramics, and more. This technology has even found an application onboard space flights. Foodstuffs can be stored as powders onboard, rehydrated with oil and water, micronutrients added, and then 3D printed into recognisable forms, like pasta.

In many contexts the terms additive manufacturing, 3D printing, rapid prototyping and rapid manufacturing, are used interchangeably. This hints at the changing role additive manufacturing has, and is, playing in the world of advanced manufacturing. It has become an essential technology highlighting the possibilities of digital transformation. 

As an industrial process, additive manufacturing offers us a new way to design and make things. It’s an approach that allows us to create complex shapes and that would previously have been impossible or extremely difficult to produce. We can create internal features within components, interlocking items and it also presents many opportunities to consolidate numerous components into a single assembly.

We tend to think of additive manufacturing as a relatively new process. It was originally developed to facilitate rapid prototyping. Engineers needed only to create a CAD model and then the 3D printer would automatically create a scale model.

As technology has developed, so the additive manufacturing has become more advanced. Nowadays, we can 3D print with many different materials, not just the original plastic composites. Additive manufacturing technology can create objects from an enormous range of materials from the very large like entire buildings, down to the very small, like carbon nanotubes.

How additive manufacturing works

Additive manufacturing is a process where a machine, a 3D printer, turns a geometry file into a series of cross-sections. The machine deposits material in the form of each of these cross sections. It then continues to lay one cross-section on top of another until the final shape has been created.

It’s a three-stage process. First you design an object, then you divide that object into a series of layers and finally print and fuse each layer or ‘slice’ into a solid object.

The design phase will often begin with a product designer working on CAD software to create a new product from scratch. There are “libraries” of preexisting designs which we can simply select from, modify if necessary, and print. Other sources of product designs come from complementary technologies like 3D scanning. Engineers can use a range of 3D scanning techniques to create a digital model of existing object. From there we can create a digital model, or digital twin, of the object and replicate it, or reverse engineer a range of modifications.

Another complementary technology is generative design. This has really come into its own now as additive manufacturing has developed. Generative design uses algorithms and AI to generate optimised designs based on input constraints like material, weight, strength, and manufacturing methods. These designs often result in intricate, organic looking shapes that are difficult or impossible to produce using traditional manufacturing techniques. Additive manufacturing, with its layer-by-layer fabrication process, enables us to create these complex forms without the limitations of subtractive methods.

With generative design and additive manufacturing, engineers can create lightweight, cost-effective, and high-performance products.

Benefits of additive manufacturing

Lightweight components

One of the big benefits of additive manufacturing is its ability to produce internal structures that maintain strength and rigidity, while using less material, think lattice and honeycomb shapes.

Unlike traditional production methods, additive manufacturing removes design constraints, enabling material to be placed only where needed. This results in a reduction in material used and benefits manufacturers by lowering material costs, reducing waste, and improving energy efficiency. This is especially important in industries like aerospace and automotive, where lighter components enhance fuel efficiency and performance. Lightweight parts can also improve product handling, shipping costs, and sustainability, giving manufacturers another competitive edge in the market.

Design freedom

Additive manufacturing offers designers the ability to focus on functionality and innovation with fewer limitations. We’ve already mentioned that this technology can create enclosed internal structures, but we can add to the list features like interlocking components, undercuts, and certain types of curved surfaces. That’s things like:

• Double curvatures on freeform surfaces
• Lattice structures with curved nodes
• Internal channels with curved paths
• Organic and biomimetic surfaces
• Asymmetric or non-repeating curvatures
• Curved surfaces with thin walls

It does all that with no tooling required. Additive manufacturing also makes it easier to build integrated moving parts, allowing designers to create assemblies with articulated components in a single print. It also supports the production of geometries optimised for performance with aerodynamic profiles and heat-dissipating surfaces. The ability to design with fewer restrictions opens the door for customisation and multi-functional parts. This design freedom drives innovation and efficiency, pushing the boundaries of what is possible.

On-demand production

Additive manufacturing enables rapid prototyping and on-demand production, which significantly reduces lead times and eliminates the need for large-scale inventory storage. Instead of relying on traditional tooling or moulds, manufacturers can produce parts directly from digital files, allowing for faster iterations during the design phase and immediate production of customised or replacement parts. This flexibility is particularly valuable for industries requiring small-batch or highly specialised components, such as medical implants or aerospace parts. On-demand production streamlines supply chains, lowers storage costs, and ensures manufacturers can quickly adapt to changing market demands or customer needs.

Additive manufacturing technologies

Applications

Additive manufacturing has become a valuable tool across industries, particularly in industrial engineering. For prototyping, it allows engineers to produce and test models rapidly, speeding up design iterations and reducing development time. This helps bring products to market faster while lowering costs. In aerospace, additive manufacturing is used to create lightweight, high-performance components such as brackets and engine parts. These reduce weight and improve fuel efficiency, meeting the industry’s demand for precision and performance.

In the medical sector, additive manufacturing is used for custom implants, prosthetics, and dental devices. These are tailored to individual patients, ensuring better fit and functionality. Surgeons also rely on 3D-printed surgical guides and anatomical models to improve accuracy in complex procedures. The automotive industry uses additive manufacturing for custom tooling, jigs, and prototypes, streamlining production processes and cutting lead times. Lightweight components enhance vehicle efficiency and meet sustainability goals.

In manufacturing, additive techniques can produce jigs, fixtures, and spare parts on demand. This reduces downtime, lowers inventory costs, and allows for greater flexibility in production. Architects and engineers use it to create detailed scale models for design validation and client presentations. In some cases, it is even applied to construction, with 3D-printed concrete structures allowing for faster and more efficient building methods.

Additive manufacturing also supports innovation in consumer goods, art, and fashion, but its industrial applications remain its strongest asset. It allows for complex geometries, material efficiency, and the production of functional, high-performance components. For industrial engineers, it provides a practical solution to challenges in design, production, and supply chain management, making it an essential tool in modern manufacturing.