10. Directed Energy Deposition Flashcards
What is directed energy deposition?
Powder or wire melted by beam or arc of energy.
What materials are DED?
Either metal powder or metal wire. sometimes polymer or ceramic.
What are the 3 types of energy source in DED?
- Laser Beam
- Electron Beam
- Plasma arc
What is the name for laser beam DED?
Laser engineered net shaping (LENS)
What is the name for electron beam DED?
Electron Beam Additive manufacturing
What are the differences of LENS and EBAM?
LENS uses powder, and a laser beam, no vacuum.
EBAM uses wire feedstock, and an electron beam, vacuum.
what are the pros of LENS over EBAM?
- no vacuum
- more precise
- no x rays generated
What are the pros of EBAM over LENS?
- better weld penetration.
- dissimilar materials possible.
- faster material deposition.
Compare feedstock types for DED.
Powder:
- Most versatile
- Most metals and ceramics are available in powder form.
- some powder wasted in process
Wire:
- No material wasted
- Higher porosity
- Harder to achieve 3d geometry
- Cheaper than powder for identical material
What are the 2 types of nozzle for DED? Compare them.
single:
- cheaper
- slower deposition
4 nozzle:
- faster deposition
- wider range of alloys
Describe the mech properties of DED materials.
- fine grain structure
- higher quality than wrought products.
- multi material products possible.
What are the pros of DED?
- Fine microstructure = high hardness
- high control of microstructure
- high density
- faster than PBF
what are the cons of DED?
- Vacuum required
- poor resolution and surface roughness
- limited part complexity compared to PBF.
What are the applications of DED?
- 3D parts
- Development of alloy materials
- Repair of existing structures
