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My understanding is that most current metal 3d printing yields items with significantly worse properties with respect to shear forces, because of how the molecu

My understanding is that most current metal 3d printing yields items with significantly worse properties with respect to shear forces, because of how the molecules align compared to when it's melted together as a whole and cooled (or something like that, I can't find the research paper someone linked to me in the past here regarding that). Do we know if this is better with respect to that?

alfalfasprout 2y ago
In theory can't the final object be tempered/annealed to achieve the desired properties?
metal_am 2y ago
Texture (the statistical arrangement of all the crystal lattice arrangements that make up a metal) can play a role on mechanical properties, but current metal AM is more than able to meet material standards. It's good to be careful with blanket statements because the most accurate answer is usually "it depends."
- prrrywinkle 2y ago
  [dead]
- WheatMillington 2y ago
  I agree we should avoid blanket statements, which is why your statement "current metal AM is more than able to meet material standards" is problematic. What standards? There is no generic "material standards" for all materials, and 3d metal printing is definitely inferior to MOST other manufacturing methods in MOST circumstances, in terms of mechanical properties.
  - Iulioh 2y ago
    I mean, we 3d print aerospace engine parts, is this "common sense" logic really true?
    - codetrotter 2y ago
      The 3D printing they do for aerospace engine parts is certainly very much different from how most metal 3d printing is done. Because the requirements are completely different, and the budgets that aerospace have available to them are insanely much bigger.
      - llm_trw 2y ago
        I was recently brought in by a friend as a consultant for a traditional machining shop buying a 3d printer, the machine looked like this: https://i.all3dp.com/workers/images/fit=scale-down,w=1200,gravity=0.5x0.5,format=auto/wp-content/uploads/2022/07/22173130/Metal-DED-printer-Additec-metal-WAAM-printer-MX3D.jpg https://i.all3dp.com/workers/images/fit=scale-down,w=1200,gr... Right now you can print aerospace quality parts on hardware that's designed for marine grade parts, which we did by testing them to failure. The only reason why the price is higher for aerospace is that you need to certify the machines and the environment in which they work and that costs an arm and a leg.
        anakaine 2y ago
        Are you able to recommend any particular low end machines to have a look at in this space?
        llm_trw 2y ago
        Low end here starts at $100k, the machines I was looking at were between 500k and 1m with service contracts.
        Joel_Mckay 2y ago
        Powder feed: https://iro3d.com/ https://iro3d.com/ metal and or ceramic slurry: https://www.rapidia.com/ https://www.rapidia.com/ Service for the SLS process: https://www.xometry.com/ https://www.xometry.com/ Or wait a bit longer for a good community design release... Have fun =3
    - Haemm0r 2y ago
  - metal_am 2y ago
    A line has to be drawn somewhere because this is a rabbit hole. Without going into the specifics of ASTM standards, etc., there are metal AM parts flying today in both air and space. IMO, that counts as meeting standards.
    - lazide 2y ago
      But which standard, or even rough category means a lot. Forged? Stamped? Die cast? Investment cast? Billet/machined? Each of those has vastly different characteristics.
- kbenson 2y ago
  I'm not sure I made a blanket statement, except with respect to my understanding, and I can assure you that I was factually correct in my assessment of my own understanding. ;) I was careful to phrase my comment in a way that I thought could lead to useful discussion, because I value that, and to note it was only my understanding, because my understanding is outdated and minimal. It just so happens that I was part of a prior discussion years ago regarding suitability of 3d printed metal parts, and found some information at that time which pointed to some of the problems they have in comparison to other methods, so was interesting in learning more.
Joel_Mckay 2y ago
Where did you hear that? In general, the issues sintered parts have are slight porosity (<3%), slow annealing cycles (internal stress), and possible problems with conventional machining. We also looked at metal-salt plating processes, and concluded the risks to the operator made it nonviable for general application. There was also the serious environmental impact risks, and that meant hazmat disposal costs etc. There are always trade-offs with any technology. Have a great day, =3
- kbenson 2y ago
  Took me a while, but I tracked down the conversation. Turns out it wasn't a research paper, and I wasn't linked to it but found it on my own in researching the discussion I was having[1]. It was an a video about engineering and cost effectiveness of sintering metals and the current downsides, which (at the time) there were attempts to counter by using specific laser patterns, but even with that the fatigue life was lacking compared to other manufacturing methods. This is, of course, four years out of date, and I can't state for certain how accurate the review of the problems that video provided were, but it did a very good job of explaining what caused those problems, so I wasn't left with many questions as to why sintering wasn't as well suited for some situations. That said, I'm not in this industry, I just noticed some relation to a prior conversation I had and the topic is interesting to me. 1: https://news.ycombinator.com/item?id=24795406 https://news.ycombinator.com/item?id=24795406 2: https://www.youtube.com/watch?v=fzBRYsiyxjI https://www.youtube.com/watch?v=fzBRYsiyxjI
  - Joel_Mckay 2y ago
    Fatigue failures could theoretically be more probable on stress-raisers around oxide inclusions. However, most modern DMLS have achieved better than >99.5% build density in an inert atmosphere, and better controlled annealing. =) The more exotic experimental processes intended for hobbyists will likely overtake industry in the next year... ;-)
xnx 2y ago
Would there still be a benefit to rapidly producing metal molds/forms for other materials?
- metal_am 2y ago
  Absolutely. Printed molds and forging dies with conformal cooling channels can decrease cycle times.
esskay 2y ago
With some of the earlier ones that may have been the case as many were simply melting small blobs of metal and dropping them onto eachother. The newer ones act a lot more like a welder. It's why it's been possible to 3d print rocket components.
kragen 2y ago
it's possible to electrodeposit metals with a variety of grain structures, including both strained and non-strained versions. strain is the main problem with processes like sls/slm
FrostKiwi 2y ago
There are so many ways to do metal 3D printing, that it really depends on technique and use-case. I can only comment on SLM (Powder is in a bed, melted by laser from above) and DED (Powder comes from a nozzle and melted by a laser from above), but you can easily move the resulting metal properties in very different directions, by adjusting an unending list of parameters. So many things happen can once when melting metal (hardening, tempering, martensitization), that you can make the result "properties with respect to shear" better or worse by tweaking the process. Finding these parameters is a research field in of it itself and whether or not properties are better or worse in "most current metal 3d printing" really depends on your use-case and material. There is no blanket statement on how the material properties will be after these processes.
dpain 2y ago
This is one of the benefits of the ECAM process happening completely at room temperature. Since the metal is deposited directly out of a liquid metal feedstock there's no thermal processing (sintering, melting, etc) which have traditionally caused shrinkage/warpage and porosity issues in other metal AM technologies. Since the ECAM process has control over the deposit at the atomic scale, an extremely high level of purity is achieved. This is very important for high performance applications requiring thermal or electrical conductivity for instance.
IWinfield 2y ago
Great question! With thermal based processes that can certainly be a problem, but it's quite different with Electrochemical Additive Manufacturing (ECAM). The ECAM process operates at room temperature and deposits material via electrodeposition - so no melting is involved! The resulting microstructure is a fine grained structure (avg. grain size ~ 500 - 1000 nm) with fairly equiaxed grains that provide high strength and isotropic behavior. So we don't see the same challenge that say a laser based process encounters due to melting and cooling. -Fabric8Labs

alfalfasprout 2y ago

In theory can't the final object be tempered/annealed to achieve the desired properties?

metal_am 2y ago

Texture (the statistical arrangement of all the crystal lattice arrangements that make up a metal) can play a role on mechanical properties, but current metal AM is more than able to meet material standards. It's good to be careful with blanket statements because the most accurate answer is usually "it depends."

prrrywinkle 2y ago
[dead]
WheatMillington 2y ago
I agree we should avoid blanket statements, which is why your statement "current metal AM is more than able to meet material standards" is problematic. What standards? There is no generic "material standards" for all materials, and 3d metal printing is definitely inferior to MOST other manufacturing methods in MOST circumstances, in terms of mechanical properties.
- Iulioh 2y ago
  I mean, we 3d print aerospace engine parts, is this "common sense" logic really true?
  - codetrotter 2y ago
    The 3D printing they do for aerospace engine parts is certainly very much different from how most metal 3d printing is done. Because the requirements are completely different, and the budgets that aerospace have available to them are insanely much bigger.
    - llm_trw 2y ago
      I was recently brought in by a friend as a consultant for a traditional machining shop buying a 3d printer, the machine looked like this: https://i.all3dp.com/workers/images/fit=scale-down,w=1200,gravity=0.5x0.5,format=auto/wp-content/uploads/2022/07/22173130/Metal-DED-printer-Additec-metal-WAAM-printer-MX3D.jpg https://i.all3dp.com/workers/images/fit=scale-down,w=1200,gr... Right now you can print aerospace quality parts on hardware that's designed for marine grade parts, which we did by testing them to failure. The only reason why the price is higher for aerospace is that you need to certify the machines and the environment in which they work and that costs an arm and a leg.
      - anakaine 2y ago
        Are you able to recommend any particular low end machines to have a look at in this space?
        llm_trw 2y ago
        Low end here starts at $100k, the machines I was looking at were between 500k and 1m with service contracts.
        Joel_Mckay 2y ago
        Powder feed: https://iro3d.com/ https://iro3d.com/ metal and or ceramic slurry: https://www.rapidia.com/ https://www.rapidia.com/ Service for the SLS process: https://www.xometry.com/ https://www.xometry.com/ Or wait a bit longer for a good community design release... Have fun =3
  - Haemm0r 2y ago
- metal_am 2y ago
  A line has to be drawn somewhere because this is a rabbit hole. Without going into the specifics of ASTM standards, etc., there are metal AM parts flying today in both air and space. IMO, that counts as meeting standards.
  - lazide 2y ago
    But which standard, or even rough category means a lot. Forged? Stamped? Die cast? Investment cast? Billet/machined? Each of those has vastly different characteristics.
kbenson 2y ago
I'm not sure I made a blanket statement, except with respect to my understanding, and I can assure you that I was factually correct in my assessment of my own understanding. ;) I was careful to phrase my comment in a way that I thought could lead to useful discussion, because I value that, and to note it was only my understanding, because my understanding is outdated and minimal. It just so happens that I was part of a prior discussion years ago regarding suitability of 3d printed metal parts, and found some information at that time which pointed to some of the problems they have in comparison to other methods, so was interesting in learning more.

Joel_Mckay 2y ago

Where did you hear that? In general, the issues sintered parts have are slight porosity (<3%), slow annealing cycles (internal stress), and possible problems with conventional machining. We also looked at metal-salt plating processes, and concluded the risks to the operator made it nonviable for general application. There was also the serious environmental impact risks, and that meant hazmat disposal costs etc. There are always trade-offs with any technology. Have a great day, =3

kbenson 2y ago
Took me a while, but I tracked down the conversation. Turns out it wasn't a research paper, and I wasn't linked to it but found it on my own in researching the discussion I was having[1]. It was an a video about engineering and cost effectiveness of sintering metals and the current downsides, which (at the time) there were attempts to counter by using specific laser patterns, but even with that the fatigue life was lacking compared to other manufacturing methods. This is, of course, four years out of date, and I can't state for certain how accurate the review of the problems that video provided were, but it did a very good job of explaining what caused those problems, so I wasn't left with many questions as to why sintering wasn't as well suited for some situations. That said, I'm not in this industry, I just noticed some relation to a prior conversation I had and the topic is interesting to me. 1: https://news.ycombinator.com/item?id=24795406 https://news.ycombinator.com/item?id=24795406 2: https://www.youtube.com/watch?v=fzBRYsiyxjI https://www.youtube.com/watch?v=fzBRYsiyxjI
- Joel_Mckay 2y ago
  Fatigue failures could theoretically be more probable on stress-raisers around oxide inclusions. However, most modern DMLS have achieved better than >99.5% build density in an inert atmosphere, and better controlled annealing. =) The more exotic experimental processes intended for hobbyists will likely overtake industry in the next year... ;-)

xnx 2y ago

Would there still be a benefit to rapidly producing metal molds/forms for other materials?

metal_am 2y ago
Absolutely. Printed molds and forging dies with conformal cooling channels can decrease cycle times.

esskay 2y ago

With some of the earlier ones that may have been the case as many were simply melting small blobs of metal and dropping them onto eachother. The newer ones act a lot more like a welder. It's why it's been possible to 3d print rocket components.

kragen 2y ago

it's possible to electrodeposit metals with a variety of grain structures, including both strained and non-strained versions. strain is the main problem with processes like sls/slm

FrostKiwi 2y ago

There are so many ways to do metal 3D printing, that it really depends on technique and use-case. I can only comment on SLM (Powder is in a bed, melted by laser from above) and DED (Powder comes from a nozzle and melted by a laser from above), but you can easily move the resulting metal properties in very different directions, by adjusting an unending list of parameters. So many things happen can once when melting metal (hardening, tempering, martensitization), that you can make the result "properties with respect to shear" better or worse by tweaking the process. Finding these parameters is a research field in of it itself and whether or not properties are better or worse in "most current metal 3d printing" really depends on your use-case and material. There is no blanket statement on how the material properties will be after these processes.

dpain 2y ago

This is one of the benefits of the ECAM process happening completely at room temperature. Since the metal is deposited directly out of a liquid metal feedstock there's no thermal processing (sintering, melting, etc) which have traditionally caused shrinkage/warpage and porosity issues in other metal AM technologies. Since the ECAM process has control over the deposit at the atomic scale, an extremely high level of purity is achieved. This is very important for high performance applications requiring thermal or electrical conductivity for instance.

IWinfield 2y ago

Great question! With thermal based processes that can certainly be a problem, but it's quite different with Electrochemical Additive Manufacturing (ECAM). The ECAM process operates at room temperature and deposits material via electrodeposition - so no melting is involved! The resulting microstructure is a fine grained structure (avg. grain size ~ 500 - 1000 nm) with fairly equiaxed grains that provide high strength and isotropic behavior. So we don't see the same challenge that say a laser based process encounters due to melting and cooling. -Fabric8Labs