Additive manufacturing with metal

Sebastian, you work with additive manufacturing as a scientist at RISE IVF in Mölndal. What is the funniest part with your job?

It has to be the variation of the work tasks. On the one hand the mix between practical and theoretical tasks that makes that I never get tired of what I'm doing. And on the other hand the variation of what companies I'm working with and what research questions I'm dealing with. Plus the working environment with a lot of innovative people around me is very inspiring.

What exactly is your research about?

In our unit we work with additive manufacturing of metals, plastic and ceramics but I work with metals. Since we work with developing together with Swedish industry there are a lot of differences in what we do. Everything from creating new alloys to adapting products for 3D-printing. We also work a lot with simulations, digitalization and atomization for additive manufacturing because it is still a new manufacturing technology. I myself am doing my PhD together with Chalmers within additive manufacturing of aluminium where I among other things investigate the mechanical characteristics of light-weight design.

What is special when you 3D-print with metal versus with plastic? How differ the techniques?

Actually, there isn't that big of a difference. Within 3D-printing there are several different techniques for how to 3D-print a component and most of the techniques can be used for the different material types. 3D-printing is building a component layer after layer and what differs is the techniques how to apply a layer. The different techniques have several advantages and disadvantages and it's important to find the right techniques for that specifik application. So the biggest difference in the end is the energy you need to melt your material, which is a big difference for plastic and metal, and it's what is crucial to decide if the techniques is going to be used or not.

How is the strength of the product affected when it is 3D-printed compared to when it is produced with conventional methods?

It varies. In many cases you can actually get better mechanical characteristics than with conventional methods and sometimes you get a better strength in the material but worse elasticity than conventional manufactured materials. An important factor is what metal you 3D-print and that you have different mechanical characteristics in different directions of the printed component. This can mean that the material is much stronger if you pull in one direction than in another direction, which can mean that you get a material that is both stronger and weaker, depending on which direction. As you understand, it can be both an advantage and a disadvantage depending on the application and it is important out of a design perspective when you develop new components for 3D-printing.

What possibilities do you see with 3D-printing in metal?

There are of course a lot of possibilities with 3D-printing. What is often mentioned is the possibility to manufacture unique and complicated geometries that aren't possible to manufacture in another way. Another possibility is that you can print on demand with a very short lead time, and the possibility to lower the amount of components in a product through combining them to a new component that can be printed. Det finns såklart otroligt många möjligheter med 3D-printing. But it is important to remember that 3D-printing in metal still is a very expensive technique and today it's hard to be competitive financially with the conventional techniques. Another opinion that I have is that I don't think that 3D-printing will take over the whole manufacturing industry in the future, but become a complement to conventional techniques.

What do you think about this manufacturing method out of a sustainability point of view? Social, economical and ecological?

Interesting question that I think we don't focus enough on today when we talk about additive manufacturing. What we often talk about is that we use less material when we 3D-print than when we use conventional methods, which has a positive impact on both economical and ecological sustainability aspects. A social aspect is that you contribute to a personal development of the employees through education and you also create new work situations. But one could also say that a social aspekt is that some work situations will disappear when there is a 3D-print value chain that can minimize the amount of steps in the manufacturing chain and minimize the amount of employees. Another ecological negative effect is how the material waste is taken care of when you can't use it for printing anymore. In the technique I work in, there is a lot of fine metal powder that you have to take care of and make sure that it's not leaks in the drain or in nature. Today there are a lot of open questions regarding sustainability which makes it even more important to think about that aspect when we develop the future industry of 3D-printing.

Do you have any recommendations when one thinks about 3D-printing in metal?

Today it is very expensive to 3D-print in metal. That's why it's very important to find the right component to find some profitability in it. Often there is no economical sustainability in it when one takes an existing component and 3D-prints it. You have to redesign the component to get the advantages. It can for example be to reduce the weight, add functions etc, that you can't get in the existing component manufactured with conventional methods. One example could be to add lattice structure in a component where normally is only "dead weight" and also add complex channels in the component close to the functional area that can be used for censoring and cooling, just as an example. Another time when 3D-printing could be good could be when you have a lot of lead times on critical components for a product, there could the "expensive" price for 3D-printing in the end become cheaper if you otherwise risk to wait for a couple of months until the supply of a component from the other side of the world.

How far are we from serial production?

I'm not super informed about that, but my understanding is that there is some serial production of 3D-printed components. Mostly it is complex components in advanced industries where you make profit of 3D-printing. But it's also used for components in the luxury segment, e.g. in expensive sports cars. What I notice to be more common and I think we will se more about in the future is that factories invest in 3D-printers and add them to their machines where they already have machines of conventional manufacturing processes and that they have Lego production of bigger parties of components for several companies.