Additive Manufacturing Is Ready For Prime Time

Although additive manufacturing (AM) accounts for only 0.03 per cent of the global production market – which is worth more than more than $13 trillion -- it has moved on from the experimentation phase and is now evolving into a booming business.

In 2016 worldwide sales will increase by around 30 per cent to more than U.S.$9.34 billion. This is the conclusion of a study conducted by the international management consultancy Bain & Co. ¹ But this is just the start. Bain & Co. reckons that annual growth rates of more than 30 per cent will continue to be achieved and the market will grow to about $16 billion by 2018. In the consultancy’s assessment, AM is on the cusp of achieving mass production.

In addition, the EFI Expert Report 2015 ² forecasts that the global market for AM will be around $28 billion by 2020.

Mass Effect

AM has reached the stage of industrial mass production.

In view of the build rates and build envelope sizes that are already possible today, AM has long since moved on from the prototyping phase. The megatrend of Industry 4.0 is now the great challenge that awaits all participants in the market.

According to Peter Sander, head of emerging technologies and concepts for Airbus, by 2018 Airbus is planning to have titanium, stainless steel, and aluminum in AM series use. Users in the U.S. aerospace industry have declared that AM is to be their standard strategy.

The challenges for economical series production play out on three levels: digitization, automation, and networking of the machines right through to the creation of a smart factory.

But to achieve this, the machines must, on the one hand, become even better, more efficient, and more economical; and on the other hand, they must satisfy the basic concept of Industry 4.0.

AM: From Trend to Boom

A number of sectors have now defined laser melting of metals as representing their strategic direction. Examples include the aerospace sector and elements of dental and medical technology. Other important sectors such as automotive are currently getting used to the concept. Here, too, AM seems to offer a promising range of future benefits.

The AM option typically is the right one whenever the additively constructed part will be better, more powerful, available more quickly, lighter, and cheaper. A study by Roland Berger shows that AM costs are currently estimated at $4.56/cm³ (for material, machine, and energy) ³ but are constantly falling, which will improve the prospect of further expansion.

Berger’s forecasts are:

* 2018 -- $2.32/cm³

* 2023 -- $1.60/cm³

From the point of view of industry, build rates are probably the most important criterion when it comes to assessing economic efficiency. The limits are continuously shifting upwards thanks to technological progress. To illustrate this point, Berger expects the following build rates:

* 2013 – 10 cm³/hour

* 2018 – 40 cm³/hour

* 2023 – 80 cm³/hour

This is an increase by a factor of 8 in 10 years. This means production on an industrial scale can be expected. Some sectors are moving away from the established applications of AM, such as rapid prototyping and industrial prototyping, in favor of series production. This is not a fad but a trend.

Market Change

In the last three to four years, numerous industries have embarked on the exploratory phase of AM. The pioneers, that is to say the innovators, are analyzing all previous structures produced by machining or casting to establish whether they can be produced by AM instead.

They have moved over to an adaption phase for the additive methods. We regard this as the first step toward industrial series production, which requires new responses from the machinery and plant engineering industry. Freedom of geometry and the potential for lightweight construction, functional integration, production on demand, time and cost savings, and considerations in relation to resource-saving and sustainable production all play a substantial role here.

Keep Design in Mind

Previously purchasers placed a conventional part on the table and asked what it would cost to produce by laser melting. What this effectively meant was the benefits of the process were not exploited.

Today designers are adopting a more systematic approach.

The performance parameters are defined and production that fits the process is developed from them. The part can be “designed” to suit AM. This does not just produce a surprising visual result.

Bionically designed lightweight components can be on average up to 20 to 30 per cent lighter than milled or cast components. In some cases, the potential weight reduction is in fact as much as 60 to 80 per cent; for example, if rectangular metal blocks are reduced down to their actual function. It is important to record the thermal and mechanical properties to determine the part requirements and then deliver them with a design that is deliberately tailored to suit the process.

Specifically this means that the parts are not only able to do more, they are also lighter and have a different geometry. Ultimately, every gram of weight saved in turn means an increase in the economic efficiency of AM.

The demand for AM capacity is growing rapidly worldwide. The on-demand and peripheral options for manufacturing mean that this applies to almost all the regions in the world. A current trend that can be seen is that processors are forming up and willing to make strategic investments in metal printing.

Ideally, two typical providers are emerging here:

1. The printing center as a service provider.
2. Industrial users that make use of their in-house development and manufacturing expertise to fully exploit their competitive advantages.

One side effect that should also be noted is that those processors that want to offer comprehensive 3-D product offerings are expanding their metallurgical and process-engineering skills, looking for networks and cooperative arrangements, and offering parts of widely varying sizes.

It is all about being a full-service provider.

It is also apparent that the processors are expanding their fleet of machinery to increase build envelope sizes and numbers. Companies with more than 20 machines are not that unusual nowadays. Both segments are developing very dynamically. All of these phenomena combined reflect the process of industrialization of AM.

What Is State-of-the-Art?

The previous machine concepts focused on build rates, build envelope sizes, and aspects of quality.

The stated objectives were largely met on the supplier and processor side, and this meant that as a first step AM was able to establish itself for prototyping and manufacturing of small batches. But the expectations placed on AM continue to rise.

What answers are the machinery and plant manufacturers offering in the medium term? Larger build envelopes? Large build envelopes for the powder bed-based laser melting of metals typically are in the 800- by 400- by 500-mm range. Even larger build envelopes are conceivable, but higher stresses are then produced in the part, and it is uncertain whether such a machine can be operated in an economical way.

In addition, smart joining techniques are also available. The industrial users are reasonably satisfied with the current state-of-the-art machines.

Are more powerful laser sources the answer? There is eager anticipation here to see where technical progress will lead, but this route alone will not be the preferred choice.

How about higher build rates? There is definitely one approach here that can be implemented quickly. The key concept is multilaser technology. However, multiple laser sources must be used skillfully to ensure that there are no curtailments to the quality of the parts, with areas of overlap and the development of soot deposits.

How Many Machines?

The following should fundamentally be stated: The current machines and installations are “island solutions.” They operate as “stand-alone” machines without really being integrated into the operational manufacturing environment.

The machines are not interlinked either with each other or with upstream and downstream manufacturing processes. They can “communicate” only to a limited extent within the digital process chain extending from design through to fabrication. In this form they are not suitable for the industrial series production of the future.

The consistent automation of manual processes is still missing. The previous sequence of setup tasks and part production in one machine results in downtimes and wastes time for the operator. As things stand today, the interlinking of the machines with one another and with peripheral devices is not yet provided.

These critical points show that we still have some way to go to achieve the objectives of Industry 4.0 in the guise of a smart factory. However, the approach also emerges from the growing number of machines that individual processors have: If more than 20 machines are in use, the amount of space required for conventional stand-alone systems increases hugely.

AM Example: Airbus

Additively manufactured series parts are taking over aviation

The aviation industry is already relying on AM series production. One example of this is a cabin bracket that connects one element in the cabin to the main structure of an airplane.

The conventionally manufactured part has been structurally modified by means of a topology optimization and additively constructed. This allows a weight saving of around 30 per cent compared to the conventional part coupled with greater resilience.

According to Airbus’ assessment of the potential, with a weight reduction of 1 ton for each airplane and a global market of about 32,600 new aircraft by 2035, there is the potential to achieve a saving of 46 million tons of kerosene with around 119 million tons of CO².

AM Example: General Electric

The next industrial revolution

General Electric (GE) refers to itself as a “Digital Industrial Company” and talks about AM as being the next industrial revolution. In 2014 the company announced that within five years approximately 80 per cent of an engine would be additively manufactured. GE also announced in 2014 that a fluid nozzle for fueling aircraft, which was previously a die-cast part, should only be produced by printing by 2016.

GE specifies that the build rate is only about 18 hours, and the number of units worldwide is around 150,000 per year, which surprises even those who know the industry.

Oliver Edelmann is vice president global sales and marketing, Dr. Florian Bechmann is head of R&D, and Oliver Kaczmarzik is technical product manager for Concept Laser, 49-9571-16790, www.concept-laser.de/en.

Notes

1. Pierluigi Serlenga and François Montaville, Bain & Company, “Five questions to shape a winning 3-D printing strategy” (September 2015 study).

2. EFI Expert Report 2015, Expert Commission on Research and Innovation, (February 2015).

3. Study by Roland Berger Strategy Consultants, “Additive manufacturing – A game changer for the manufacturing industry?” (Munich, November 2013).