Zare GM Andrea Pasquali Explains Why Aluminum is the AM Material of the Future

With over 50 years of activity in the field of precision mechanics, Zare is today the most experienced non-specialty metal AM service bureau in Italy and one of the most advanced worldwide. Located in the heart of Italy’s “Motor Valley”, the company began implementing metal AM for rapid prototyping in 2009 and opened an area for post-processing, finishing and medical and dental models in 2011. Today, with XLine 2000 large format production systems from Concept Laser as well as SLM Solutions and Renishaw, it is evolving into a full fledge AM factory. During the work conducted on the latest market report and forecast on Aluminum AM for SmarTech Publishing, I had the opportunity to speak with the company’s GM Andrea Pasquali about his vision for the future of digital manufacturing. The following interview begins with Zare’s unique role as APWorks partner for the development of Scalmalloy SLM 3D printing parameters and goes on to illustrate where the future of AM production is headed.

Which do you see as the primary applications for Scalmalloy aluminum alloys?

“Mostly for space and aviation applications, I don’t see it as having more “day-to-day” applications at this time. It is mainly an issue of costs, both in terms of raw materials and production processes. It is quite a slow production process compared to traditional aluminum. At the same time it registers mechanical performances that are double compared to standard aluminum alloys such as AlSi7 and AlSi10. It suffers a little at high temperature but it’s great challenger to titanium.”

Which are the ideal applications for Scalmalloy?

“It is ideal for all those lightweigthing applications where aluminum is not strong enough and titanium is too expensive. Scalmalloy gives us a weight that is comparable to aluminum with more strength. Not as strong as titanium but enough for many parts. It’s not going to be a materials for mass applications but it will be used to make a growing variety of advanced parts.”

Which materials do you see as ideal for larger batch AM productions?

“We are working on parameters for more traditional and affordable aluminums. We have not seen any current use of these alloys in AM and they may not be very easy to 3D print, since we are talking about alloys with a high copper content. We are working on these as lower priced material to use in greater quantities for part production. Another aspect we are studying closely for the future are composite alloys of aluminum and ceramics.”

How much do you use aluminum at Zare compared to other metals?

“For us it represents as much as 50%-60% of material demand and I predict that it will be used more and more in the future for additive manufacturing. There are two primary reasons for this. The first is that costs will continue to decrease, both in terms of raw material and production processes. The second is that the truth is that, starting with the same materials, our additively produced parts guarantee superior mechanical performances. The same alloys, produced with traditional methods, show about 30% less mechanical performance due to the difference in cooling times. The parts are very strong but also very brittle.”

How do you deal with all the challenges of processing aluminum powder by AM, such as oxidation and heat absorption and light reflection?

“Many of these aspects depend by how you approach AM. Zare is a factory, we have several certifications and we employ a wide variety of production methods. We tackle any issue from a scientific point of view. Before we print a material we conduct a lot of research and analysis of the issues. Especially with aluminum, if you undergo this type of preparation you can address 90% of the issues that the material presents. In the end there are many similarities to how many alloys behave so our experience helps us when developing new parameters. We do a lot of R&D and we are able to address pretty much every issue that can arise. Paradoxically aluminum is even easier to process than certain nickel and titanium alloys.”

Have newer machines and materials made 3D printing easier of more complex?

“This is quite a relevant issue. On the one hand, if you have machines that are old – which in AM means that they are 2 or 3 years old – working with aluminum alloys is very hard. On the other hand the new systems are so much more technologically advanced that developing the correct parameters for each material take a lot more work than it used to. Because we have  so many systems and we consume so much materials we have to buy the powders from third parties suppliers and work on parameter development. Today’s systems have multi-laser systems and built in 3D optics. We do have more powerful software tools to work with but they can only get you so far.”

Have you had a chance to evaluate new upcoming MIM-based AM technologies such as Desktop Metal’s Production System and HP’s upcoming metal system?

“I think that’s going to be the future of AM production. In particular we really admired Desktop Metal’s vision for the Production System. Today at Zare we use powder bed fusion systems however we are convinced that in the long terms future the majority of AM production will be carried out with binder jetting technologies. We have already asked to work with both Desktop Metal and HP on the upcoming systems and to help them with material and process development. It is going to take a couple of years and I don’t think these systems will ever replace powder bed fusion as much as expand AM capabilities beyond the current limits in terms of productivity.”

Do you think that it will be possible to overcome the additional challenges of processing aluminum and titanium with binders and furnace post processing?

“Working with aluminum and titanium is never easy. I have seen parts made of steel and nickel as well as copper alloys. It will take time and work. Initially I was unsure about the requirements for debinding and furnace sintering but I have become convinced that this type of post processing is not all that different – in terms of time and costs – from the post processing that is necessary for support removal in powder bed fusion. The systems cost-effectiveness should make for the additional time necessary for furnace processing. It will take some time. Having already worked with HP’s polymer production systems, we know that many of the current challenges in additive manufacturing can be overcome.”