Module 1: AM technologies Flashcards
What are the challenges for space materials and processes?
1) Low mass
2) Small production series
3) Very high reliability
4) Limited Manufacturing Processes
5) Small geometries
6) Very high performances
7) Challenging material procurement
Why is additive layer manufacturing (ALM) used?
1) AM is very wel fitted to space hardware -> small production series
2) Very complex geometries possible
3) Large variety of materials (metals, polymers, composites, ceramics for space but also food, living cells and organs)
4) Dimensions range from a few micrometers to meters
5) Gains in performances with 2 digits (mass savings, lead time, suprress complex assemblies and controls)
6) Environmentally friendly
7) Could be used for in-orbit or on other planets
What is the manufacturing route definition for metal and ceramic parts?
Metal Parts:
Powder procurement -> SLM -> Heat treatment (stress relieving, HIP, T6) -> CT -> US cleaning -> chemical polishing -> milling/tapping -> plating -? tuning
Ceramic Parts:
Binder/Ceramic power -> Mixing to slurry -> 3D print -> cleaning -> debinding & sintering -> CT -> Plating -> Connector mounting -> Tuning
What are some benefits of ALM?
1) Design freedom
2) Performance impovements (mass, RF, performance)
3) Co-design considering RF, thermal and mechanical constraints
4) Merging of complex sub elements into one
5) Lead time reduction (from concept to manufacturing)
What was the benchmarking done by ESA?
Benchmarking of:
- AM powders
- produced materials
- post-processing techniques
- AM machines
eg for powder procurement specification, appearance, flow properties, PSD laser, morphology, chemistry contamination and porosity was examined. Testing of different materials for fracutre test and fractography signatures for a range of AM materials and build conditions.
What are the targeted application and expected benefits of Hybrid AM?
- Targeted applications of AM hybrid components: Liquid propulsion elements
- Expected benefits are:
1) Cost reduction
2) Lead time reduction
3) Complex parts with AM
How can we benefit from ISS polymers/metalic printers?
1) Revise mission logistics
2) On demand production of spare parts on orbit/planet, remotely designed
3) On orbit manufacturing and launch of small satellites
What is the definition of Additive Manufacturing?
A process of joining materials to make objects from 3D model data, usually layer upon layer.
What are the essential properties of metal powders?
1) Chemical composition
- Readily alloyed feedstock for atomization
- Alloying by mixing two or more powders
2) Flowability
- Particle size
- Size distribution
- Shape
What is cladding?
Cladding processes:
- Molten pool is created by a laser, electron beam, or plasma
- Powder or wire is guided into the melt pool
- Other designations (DirectMetalDeposition, LaserEngineeredNetShaping,WireArcAdditiveManufacturing)
Advantages:
- Large building volumes, high deposition rates, different feedstocks
Disadvantages:
Roughness, resolution, geometrical complexity
What is Wire Arc Additive Manufacturing?
The use of an electric arc as a heat source to generate 3D ojects depositing molten metal in superimposed layers
Advantages:
-High deposition rates
- High material efficiency
- No defects
- Low part cost
Disadvantages
- Medium to low level of complexity
Rolled and heat treatment is used to remove defects.
What is powder bed processes: electron beam melting
- Molten pool is created via an electron beam under vacuum
- Powder is applied layer wise
Advantages:
- Several molten pools can be maintained
- High build up rates
Disadvantages
- Roughness
- Resolution
- Geometrical complexity
What is powder bed processes: selective laser melting?
- Molten pool is created via a laser beam under inert gas atmosphere
- Powder is applied layer wise
Advantages
- Very high geometrical freedom
Disadvantages
- Build up rate
What does the SLM consist of?
1) Part
2) Dispenser platform
3) Building platform carrier
4) Building platform
5) Collector platform
6) Recoater blade
7) Recoater
