Additive manufacturing and 3D printing in manufacturing

Additive manufacturing (AM) and 3D printing haven’t reached an inflection point yet in Industry 4.0 as some expected would be the case by now. However, things are changing despite standardization and business challenges. Additive manufacturing remains a game-changer although its perceived benefits for smart factory initiatives might need more attention.

A quick reminder of what additive manufacturing and 3D printing are before looking at evolutions and challenges. Additive manufacturing, often interchangeably used with the more popular term 3D printing, refers to a range of manufacturing technologies that use additive processes to construct physical objects by adding minuscule layers (hence additive).

Additive manufacturing offers many benefits in comparison with subtractive manufacturing, which is seen as the opposite of it, and, as the name indicates, uses techniques and tools to remove pieces of material to get the final physical object.

Rapid increases in production speeds combined with major advances in 3D printing materials is enabling the use of 3D printing in manufacturing across a wider range of applications (Tim Greene, IDC)

An additive manufacturing definition from NIST: ‘Additive manufacturing fabricates parts by building them up layer-by-layer, as opposed to cutting material away or molding it’.

Physical objects are 3D objects such as parts or products which can take many shapes for several purposes across multiple potential applications. Additive manufacturing can also be viewed as a way to turn a digital model (of the object to be constructed) into a physical one since it starts as a (3D) software design. You see the multiple benefits in working this way, especially for parts and products that are hard to construct.

Additive manufacturing and 3D printing

Additive manufacturing as an Industry 4.0 ‘technology’

Additive manufacturing doesn’t replace other manufacturing methods (at least not for many years to come, and there is this thing called hybrid) but leads to a wealth of new opportunities. Moreover, some objects would be almost impossible to make without additive manufacturing.

Additive manufacturing and 3D printing are used in multiple domains (healthcare, construction, retail, defense, pharma, automotive industry, aerospace, making parts in close to any area you can imagine, including human tissue and food, smart manufacturing). They are also the subject of intensive research and development (methods, materials, new techniques, application areas, etc.).

Given its inherent capabilities and benefits, additive manufacturing – or 3D printing if you prefer – is often touted as a revolution across industries and, of course, in smart manufacturing. Additive manufacturing is also typically mentioned as one of the main Industry 4.0 technologies that have an important place in the smart factory (it is not one technology, however, to be precise, just as the Internet of Things, the cloud, digital twins and other so-called 4IR technologies aren’t one technology).

Additive manufacturing and 3D printing are not the same, even if both terms are used interchangeably. There are still debates on when to use one of both terms. Which term you hear will also depend on whom you talk with. Oh, and there’s also 4D printing with time being the fourth dimension. In manufacturing, leading use cases for 3D printing are prototypes, aftermarket parts, and parts for new products (more below).

Perceived benefits of additive manufacturing in smart factories

Given the fact that AM is such a broad field of applications and methods, it isn’t really correct to talk about state of additive manufacturing and 3D printing in the manufacturing industry in general. Some areas, such as on-demand additive manufacturing, metal 3D printing and specific use cases as just mentioned are more important, for instance.

Additive manufacturing is the general term for those technologies that based on a geometrical representation creates physical objects by successive addition of material. These technologies are presently used for various applications in engineering industry as well as other areas of society, such as medicine, education, architecture, cartography, toys and entertainment (ISO/ASTM 52900:2015)

Still, here is one source that gives an idea of additive manufacturing and 3D printing in the manufacturing industry. In its ‘Smart factories @ scale‘ report, the Capgemini Research Institute found that the overall adoption of several technologies so far has been low. The report, based on a survey of 1,000 manufacturers, conducted in the Spring of 2019, found that, on average, 23 percent of production facilities are using additive manufacturing.

While that’s lower than other technology solutions, that is actually pretty high when looking at some of those. Industrial IoT systems, for instance, are deployed by 32 percent of the production lines on average and analytics and AI (as one category) by 31 percent.

However, in a chart that shows the relative positioning of deployed technologies versus their perceived benefits, additive manufacturing isn’t positioned all too well. The chart uses two axes: the share of facilities leveraging the technologies and the perception executives have with regards to their potential benefit.

On the level of perceived benefits by decision makers in manufacturing, additive manufacturing only scores better than plant digital twins and automated guided vehicles.

The executives participating to the Capgemini Research Institute smart factory survey have a rather low perception of the benefit potential of additive manufacturing - source and full report in PDF
The executives participating to the Capgemini Research Institute smart factory survey have a rather low perception of the benefit potential of additive manufacturing – source and full report in PDF

All other technologies/applications, which include smart energy management, track-and-trace, remote monitoring, PLM, MES, SCADA and even the augmented worker (AR/VR), score better with regards to those perceived benefits.

While, again, these are obviously averages and not all facilities might have the same case for additive manufacturing, this doesn’t look all too promising for additive manufacturing in the shorter term. It could mean that, despite the fact that AM is moving more into factories and production lines, the slower than expected progress with regards to the ‘technology’ as we’ve seen in previous years might still last a bit; at least in some verticals, the context of smart factories and some regions as in the US the AM industry seems to be doing well. All, of course, also depends on the specific vertical. As you can read in our example below, the automotive industry is one where additive manufacturing is increasingly used on top of some others mentioned before.

It’s also not that the benefits aren’t there or that there isn’t room for digital transformation by leveraging additive manufacturing and – in a broader scope of applications – 3D printing. However, the priorities seem to be elsewhere for now, certainly for the executives surveyed by Capgemini. Finally, it should also be noted that, per various surveys, there seems to be a high willingness among small and medium business, certainly in some European countries, to embrace additive manufacturing with cost-efficiency as one of the drivers.

3D printing spending and additive manufacturing industry data

According to IDC, discrete manufacturing will be the main industry for the 3D printing market until at least 2020 by when global spending on 3D printing is expected to reach nearly $22.7 billion.

Per IDC, benefits of 3D printing in manufacturing that drive the market (with discrete manufacturing leading and process manufacturing on the rise) include rapid increases in production speeds. In combination with advances in printing materials, this enables a broader number of manufacturing applications with the benefits of customized and cost-effective printing, of course remaining key.

Discrete manufacturing accounts for over half of all 3D printing spending during the forecast period (hardware, software, services and materials), followed by healthcare providers. Next comes education, followed by professional services and consumers (where we don’t talk about additive manufacturing).

The importance of 3D printing should also increase in process manufacturing since IDC expects process manufacturing to replace consumer spending on the fifth spot from a spending perspective by 2022, even if the industries that will see the fastest growth in 3D printing spending over the five-year forecast are healthcare (29.8% CAGR) and transportation (28.3% CAGR).

From a use case perspective, the primary use cases for discrete manufacturing (which are the primary use cases for 3D printing overall), prototypes, aftermarket parts, and parts for new products now account for over 40 percent of spending.

According to the Wohlers Report 2019, the additive manufacturing industry grew by almost 62 percent over 2017 and 2018, impressive growth caused by several factors strengthening each other and with record growth in the materials segment, an indicator of the growing use of additive manufacturing for production applications.

The report also found that, while industrial system manufacturers grew notably, desktop 3D printing systems saw significant decline in annual growth.

Example of 3D printing in manufacturing in practice

Cars and other vehicles consist of multiple parts. So, it’s probably not a surprise that the automotive industry is increasingly leveraging additive manufacturing.

A 3D-printed window guide rail for the BMW i8 Roadster in series production since 2018
A 3D-printed window guide rail for the BMW i8 Roadster – in series production since 2018

One example is the BMW Group that started using additive manufacturing in 2010, initially for the production of smaller series of components. However, end of 2018, the company celebrated its one-millionth 3D-printed component, the second one for its BMW i8 Roadster. In only one year, the company increased the output of 3D-printed components with over 40 percent.

The 3D-printed part is used in series production and that’s increasingly where the company will leverage additive manufacturing. Moreover, in this industry where technology is a key differentiator from a consumer and brand perspective, 3D printing techniques have also been tested for personalization purposes. They will increasingly be used in that regard as well.

You can read more about it in our article ‘How and why BMW Group uses 3D-printed components’.

Additive manufacturing definitions and types

A few words with regards to additive manufacturing definitions and techniques. As mentioned earlier, NIST (US National Institute of Standards and Technology) defines additive manufacturing as follows: ‘Additive manufacturing fabricates parts by building them up layer-by-layer, as opposed to cutting material away or molding it.’

This is more or less the same as the ASTM F2792 Standards, which defined additive manufacturing as ‘a process of joining materials to make objects from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing methodologies’.

Just like NIST and several others (there are ample evolving standards regarding additive manufacturing), ASTM International has been working on standard terminology for additive manufacturing technologies for many years. The latest standard was withdrawn in 2015 when the ISO/ASTM 52900:2015 standard ‘Additive manufacturing — General principles — Terminology’ was published. At the time of writing this, that standard was under review, as well. A preview can be checked here.

For an overview of various additive manufacturing technologies (rather, seven families, and the and the hybrid AMBIT created by Hybrid Manufacturing Technologies), based upon ISO/ASTM 52900:2015 (so, previously, ASTM F2792) check out the infographic below from Hybrid Manufacturing Technologies, which you can download in PDF here.

7 families of additive manufacturing - source courtesy and larger printable version in PDF Hybrid Manufacturing Technologies
7 families of additive manufacturing – source, courtesy and larger printable version in PDF by Hybrid Manufacturing Technologies

Based upon the graphic the families of AM are:

Vat Photopolymerization

A vat of liquid photopolymer resin is cured through selective exposure to light (via a laser or projector) which then initiates polymerization and converts the exposed areas to a solid part.

Powder Bed Fusion

Powdered materials is selectively consolidated by melting it together using a heat source such as a laser or electron beam. The powder surrounding the consolidated part acts a support material for overhanging features.

Binder Jetting

Liquid bonding agents are selectively applied onto thin layers of powdered material to build up parts layer by layer. The binders include organic and inorganic materials. Metal or ceramic powdered parts are typically fired in a furnace after they are printed.

Material Jetting

Droplets of material are deposited layer by layer to make parts. Common varieties include jetting a photcurable resin and curing it with UV light, as well as jetting thermally molten materials that then solidify in ambient temperatures.

Sheet Lamination

Sheets of material are stacked and laminated together to form an object. The lamination method can be adhesives or chemical (paper/plastics), ultrasonic welding, or brazing (metals). Unneeded regions are cut out layer by layer and removed after the object is built.

Material Extrusion

Material is extruded through a nozzle or orifice in tracks or beads, which are then combined into multi-layer models. Common varieties include heated thermoplastic extrusion (similar to a hot glue gun) and syringe dispensing.

Directed Energy Deposition (DED)

Powder or wire is fed into a melt pool which has been generated on the surface of the part where it adheres to the underlying part or layers by using an energy source such as a laser or electron beam.This is essentially a form of automated build-up welding.

Hybrid AM

Laser metal deposition (a form of DED) is combined with CNC machining, which allows additive manufacturing and ‘subtractive’ machining to be performed in a single machine so that parts can utilize the strengths of both processes.