The Quality Of Metal 3-D-Printed Objects

Looks like it’s about to exceed any other fabrication technology:

“We can now control local material properties, which will change the future of how we engineer metallic components,” Dehoff said. “This new manufacturing method takes us from reactive design to proactive design. It will help us make parts that are stronger, lighter and function better for more energy-efficient transportation and energy production applications such as cars and wind turbines.”

The researchers demonstrated the method using an ARCAM electron beam melting system (EBM), in which successive layers of a metal powder are fused together by an electron beam into a three-dimensional product. By manipulating the process to precisely manage the solidification on a microscopic scale, the researchers demonstrated 3-dimensional control of the microstructure, or crystallographic texture, of a nickel-based part during formation.

Crystallographic texture plays an important role in determining a material’s physical and mechanical properties. Applications from microelectronics to high-temperature jet engine components rely on tailoring of crystallographic texture to achieve desired performance characteristics.

“We’re using well established metallurgical phenomena, but we’ve never been able to control the processes well enough to take advantage of them at this scale and at this level of detail,” said Suresh Babu, the University of Tennessee-ORNL Governor’s Chair for Advanced Manufacturing. “As a result of our work, designers can now specify location-specific crystal-structure orientations in a part.”

This will be key for human expansion into space.

5 thoughts on “The Quality Of Metal 3-D-Printed Objects”

  1. SpaceX has been 3d printing their Draco thrusters by laser sintering Titanium powder. If electron beam melting can give precise control over the microstructure of Nickel, then it should be possible to 3D print a Nitinol structure out of Nickel and Titanium powders. This opens up the possibility of all sorts of exotic alloys being produced precisely where they are needed in a finished product.

  2. I really hate that I’m forced into the position of wet blanket because I am a fan of 3D printing.. ‘Key’ is overstating it. Useful would be more accurate. Asimov had a short story where he warned that we could lose history because of the pace of technology changes. Already we have a generation (like those MIT analysts that wrote of TRL) that are unaware of current TRLs. Or as two said, why would you want to get rid of something as valuable as O2, but if you did, have you considered candles?

    Does additive manufacturing make machinists obsolete? I don’t think so. But it could make people think nothing else works when options haven’t gone anywhere. Programmers are highly susceptible to this kind of erroneous thinking.

    1. “‘Key’ is overstating it. Useful would be more accurate.”

      It may be key in one fashion. For the last 5 years a good retired engineering friend of mine would always interrupt my enthusiasm for 3-d printing with, “Nothing you’ve said tells me how I’ll get a part with the characteristics of a well-forged piece that has a small crystalline structure *because* it has been forged with a 50 ton steam hammer!” Many will argue against space manufacturing using exactly this logic, essentially that since it takes hundreds to thousands of tons of machinery to make a fully equipped production shop here at the bottom of the gravity well, then it will require lifting that much into any orbit you want to do space manufacturing in.

      This sort of advance will be a key in answering John’s next blast about forging, …and equivalent advances will be needed in surface treatments, etc. A further interest will be how long it takes 3-d printing to achieve fine enough control to contribute to technologies like the Greer Group’s architectured nano-materials at Caltech. They’ve already been doing trusses with tube segments 5 microns long, and 25-75 nanometers thick tube walls. *That* will require truly fine control of the electron beam, …or the ion beam by then, possibly.

      1. And there is enough material out there in the Solar System to make more 50 ton steam hammers than there are grains of sand on Earth’s beaches.

  3. This technique isn’t new or specific to 3D printing (although it can be more fully utilized with it).

    Some Japanese knife makers use “SG2” steel for high-end knives; as I understand it, a mix of steel powders with different (carefully selected) microcrystalline properties are sintered together and then machined conventionally. The resulting structure would be difficult or impossible to produce with conventional tempering techniques.

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