Advantages of Additive Manufacturing
Why Consider AM?
Technology has changed substantially with additive manufacturing (AM), just in the last 5 years. AM pricing is dropping fast to compete with traditional forming methods, but it only goes so far if the design isn’t updated too. Future-proofing low volume products nowadays means redesigning for AM to position for the advantage later. This is a cost/investment you’ll need to calculate.
In the lead time department, AM has long held the advantage for prototyping. With engineering grade materials (significantly, composites and metals) now available, however, it’s no longer just for prototyping. If you select AM for production, it means you can use prototype parts as the qualification test articles! That production lead time and lack of MOQ (typically) mean that you can also reduce inventory levels and order parts just in time.
If sales volumes are expected to be high, then AM *might* not be the right solution to meet demand. Even in these rare cases, though, AM can be useful in making blanks and tooling; chances are good your casting/mold house will be taking advantage of that. Sand cast blanks need not be fully dense parts (or even metal), so designing them for AM can reduce tool costs.
Which AM Technology?
Different AM technologies drive different design considerations. What works in powder bed metallurgy may not work in DED/FDM. The same applies to the constraints. Nihilo specializes in DED/FDM integrated with hybrid machining. But if you need help designing for any manufacturing method, Nihilo is happy to provide fractional engineering design services.
The table below gives a rough idea of relative comparison of factors across some of the available technologies. Obviously, you’ll need to research the actual numbers for your particular part.
|Manufacturing Technology||Cost/ part||Tooling||Resolution||Buy/Fly Ratio||MOQ||Lead Time|
|AM Binder/Ink Jetting||$$||N/A||High||Med-Low||Applies only for small parts||2 wks|
|AM Powder Bed -SLM or EBM||$||N/A||High||Med-Low||Applies only for small parts||2 wks|
|AM Extruded + Post Sintered||$||N/A||Med||Low||N/A||1-2 wks|
|AM Direct Energy Deposition (DED)||$||N/A||Med||Low||N/A||<1 wk|
Part size plays a significant role in cost. Powder bed and jetting technologies tend to have size limits, but usually offer better resolutions for higher tolerance small parts. Because they run in batches, especially for small parts, MOQ applies, but powder bed/jetting can also offer cost savings (at the expense of lead time). Extruded parts are likewise limited in size by heat treating furnace constraints, so DED is often best option for larger parts, especially when high levels of complexity make machining expensive and long lead.
Once you’ve done your homework and crunched the numbers, you can take the next steps in getting those parts designed and qualified. Note that qualification/part certification is not listed here, as it is a cost regardless of manufacturing selection, but if you are interested in what that process looks like for AM parts, check out our article Certifying Additive Manufactured Parts For Aerospace How Difficult Is It?