AM of Metals Flashcards
Advantages
More lean:
Reduces lead times
Manufacturing on demand
Manufacturing products at internal/external customer locations to reduce shipping and logistics expenses
Reducing waste material output: only use the material for part and support build
Design iteration is accelerated and product design changes can be included up to the point of manufacture
Subcomponents can be eliminated to manufacture single parts
Mass customise production parts
Remove tooling limits to manufacture complex geometries
Disadvanatges
High cost of machines and feedstock materials
Frequent inconsistency and build failure when compared to traditional manufacturing methods
Under-developed quality assurance processes
Lack of technical or operational knowledge with personell
Slow build speeds and restricted build volumes
Post build finishing
IP Theft
Business Model
Razor and Blade: distribute the printer hardware and compatible materials to the end user
Open: Instead of locking in consumers, opt for an open platform in which third party materials may be used without danger of rendering the warranty void.
Powder Bed Fusion
Direct Metal Laser Sintering
Laser rastered across the surface of a bed of metal powder to sinter the particles together. The build platform is lowered and a new layer of powder is rolled on top
High resolution and lower price than comparable metal printers
Post-processing is required to render objects fully dense and remove internal stress
Fine powders are explosive
If you integrate with simulation software, it can help reduce material waste
Could have a desktop version
However, new metal printing technologies coming to market in 2017 offer lower price points and higher build speed
Electron Beam Melting
Electron beam rastered across the surface of a powder bed under controlled reduced pressure He environment to melt the metal particles together. The build platform is lowered and a new layer of powder rolled on top.
Can have coarser powders and can stack components for increased productivity
No residual stress from sintering
Expensive and higher flow rates require
Coarser powder = lower resolution
Strong market demand for smaller printers
A key patent is due to expire soon
Binder jetting processes that build in titanium offer higher productivity
Directed Enrgy Deposition
Blown Powder
Metal powder blown into a laser beam to weld particles to the surface.
Can be used to repair objects or selectively deposit high cost materials
Can deposit material in non line of sight areas
Combine with CNC milling
Slow build speeds and less suitable for building entire components
Different materials could be blended to print objects with graded materials
Powder bed fusion is more suitable to building entire components
Welding
Metal wire is fed into the focal point of an energy source and fused to the surface of the workpiece.
Large build volume and fast build speeds
Welding wire consumables are less costly and produce less waste compared to powder
Low accuracy due to wire feedstock
Large machines
Oil and gas could benefit from this
Binder Jetting
Metal Binder Jetting
Aqueous binder is ink-jetted into a bed of metal powder. The resultant green part is sintered and debound
Fast build speeds
No support structures required
Fine resolutions allowed
Limited metal powders
If Ti is possible, the aerospace, medical and automotive industries would benefit
Due to the debinding phase, there are normally impurities found in the products
Hard to get uniform heating which would case stresses and distortions
Some DMLS have a lower price point
Sand Binder Jetting
Organic binder deposited through inkjets into a bed of silica powder. The green part is removed and used as either a mould or a core.
Supports not required
Large build area
Unprinted sand can be recycles
Indirect process for metal part manufacture.
Excessive binder application increases the strength of moulds, but vaporisation damages structural integrity
Oil and gas could benefit from this
Sheet Lamination
Sheet lamination is a type of additive manufacturing (AM) process used to create three-dimensional objects layer by layer by laminating sheets of material together. In sheet lamination, thin layers of material, typically in the form of sheets or foils, are bonded together using various techniques to build up the desired shape.
There are several methods of sheet lamination, each with its own unique approach to bonding and shaping the layers of material. Some common sheet lamination techniques include:
- Ultrasonic Additive Manufacturing (UAM): In UAM, thin metal sheets are bonded together using ultrasonic welding. A sonotrode applies high-frequency ultrasonic vibrations to the interface between the sheets, causing them to bond together through localized heating and plastic deformation. The process allows for the creation of complex metal parts with good mechanical properties.
Can embed electronics
Fully dense objects
CNC milling required for each layer
Potential anisotropy
- Laminated Object Manufacturing (LOM): LOM involves cutting or etching thin layers of material (such as paper, plastic, or metal foil) into the desired shape using a laser or knife cutter. The layers are then stacked and bonded together using heat, pressure, or adhesive to create the final 3D object. LOM is often used for rapid prototyping and producing large, lightweight parts with low cost and fast build times.
- Electrostatic Laminated Object Manufacturing (ELOM): ELOM is similar to LOM but utilizes electrostatic forces to bond the layers of material together instead of heat or adhesive. Electrostatic charges are applied to the material layers, causing them to adhere to each other when pressed together. ELOM can be used with a variety of materials, including paper, plastic, and metal foils.
- Composite-Based Additive Manufacturing (CBAM): CBAM combines layers of reinforcing fibers (such as carbon fiber, fiberglass, or Kevlar) with thermoplastic or thermoset resins to create composite parts. The layers are laid down and consolidated using heat and pressure, often in a heated press or mold. CBAM enables the production of strong, lightweight, and structurally complex composite parts for aerospace, automotive, and other industries.
Sheet lamination processes offer several advantages, including the ability to produce large parts with minimal material waste, low equipment costs, and compatibility with a wide range of materials. However, they may also have limitations such as limited resolution and surface finish compared to other AM processes like stereolithography or selective laser sintering. Overall, sheet lamination techniques are valuable additions to the arsenal of additive manufacturing technologies, offering unique capabilities for specific applications in various industries.
New Metal Plating Processes
Metal and Polymer Filament
Metal powder-charged thermoplastic rods are extruded through a heated nozzle. The tool head is affixed to a gantry which moves on the Y-axis. The green part is washed in a debinder to remove some polymer before being sintered.
Lower price point and inert gas not required
Slow build speed with poor precision
Limited to non reactive metals
Could expand to include Ti and Al
Metal and polymer filament may not be cheap enough o compensate for limited capabilities
Vat Photopolymerisation: Direct Light Processing
UV light is projected onto a slurry of steel particles suspended in a photosensitive resin. The slurry is continuously refreshed using a conveyer. The green part is sintered after curing.
High precision
Less expensive material and cheaper printer
Requires a furnace
Toxic resins
Limited to non-reactive metals
Material Jetting: Nanoparticle Jetting
Two nanoparticle suspension cartridges are loaded to the printer, one containing the metal nanoparticles dispersed in an aqueous carrier and the other the support material. This is deposited through inkjet nozzles.
High precision
Can print hard materials and there’s no handling of metal powders
Proprietary metal cartridges likely expensive
