ExOne is a company that has over 20 year's experience in the 3D printing method of binder-jetting, so when it launched its Innovent+ platform earlier this year which was capable of printing metal injection moulding (MIM) powders, there was much buzz. So much buzz and interest that the company has already scaled that technology up into the new X1 25PRO platform, parts from which the company was showcasing at Formnext 2018.
I caught up with ExOne's Chief Commercial Officer, Jared Helfrich at the show to talk more about the system:
"The X1 25Pro is essentially a scale-up of the Innovent+ system; it prints using very fine MIM powders - you're talking nine microns - it is a mid-size production machine, and it enables you to take all of your process settings, everything you've learned from Innovent+ and have a more volumetric output."
The system prints using the MIM powders such as 136L, 304 L, and 17-4PH stainless steels; Inconel 718 and 625; M2 and H11 tool steels; cobalt chrome; copper; tungsten carbide cobalt; and many more. It combines these powders with a binder to print a green part, that is then sintered leaving a fully dense part.
"The powder metallurgy of MIM powders is well known," says Jared. "[When sintered] you're going to have a uniform shrinkage that is predictable, you'll make sure you know what the scale is but after that it becomes a repeatable process. You're looking at anywhere from 17-20% shrinkage, but it is uniform, well-known and repeatable."
What is remarkable about the parts Jared shows me is the surface finish; the parts are smooth and involve a threading system that fits together like a good quality nut and bolt from a hardware store. I asked the question, what post-processing steps were taken after sintering?
"None," explained Jared. "You're looking at parts printed in very high resolution with really tight tolerances. Along with a wide variety of materials, the big benefit is the surface finish, the surface quality and full density single alloys."
ExOne has a long history in binder-jetting and with the X1 25PRO system and the likes of its sandcasting S-Max system, those looking to manufacture in metal now have a broad church from which to choose.
"There is a crossover point where the size or the scope of your part lends itself more to casting," says Jared. "We are experts in both; we have the moulds and cores for castings that's aluminium, irons and steels and then on our direct side you've got very high-end materials, different part applications that lend themselves to that. With the spectrum of those two technologies, ExOne can cover a lot of manufacturing."
ExOne will begin taking orders for the X1 25PRO system immediately. Customers will have the opportunity to see the X1 25 PRO on display at the RAPID + TCT 3D event in Detroit on May 21-23, 2019.