3D printing of metals is facilitating the transition to additive manufacturing from rapid prototyping. Printing in plastics has its place in prototyping and education, but metal printing has allowed the technology to be adopted for part production in the aerospace, orthopedic, dental and jewelry industries and is now being developed for the oil and gas, printed electronics, and general engineering industries.
The key advantages are the same for all 3D printing technologies, but minimal material wastage becomes particularly important when using titanium powders costing $300/kg. Minimizing the buy-to-fly ratio, and light-weighting the parts to save fuel costs and carbon emissions are critical in the aerospace industry.
2014 saw unprecedented shipments of metal printers
The total installed base and sales of 3D printers during 2014, from the new IDTechEx report 3D Printing of Metals 2015-2025 shows that 2014 saw unprecedented shipments of metal printers, as companies ramp up from research into production. The installed base of 3D metal printers increased by 43% from 2013 to 2,635 units in 2014. EOS are the market leader in terms of installed based, followed by 3D Systems and then concept Laser. There are also many new companies entering into the space, offering different technologies or lower price points. The race for a consumer-level metal 3D printer is well underway.
SLM will remain dominant
The state of the market data and forecast show that Selective Laser Melting (SLM) technology is, and will remain, dominant over the next ten years. It is the most established technology, having been first commercialized by EOS in 1990, and so most developed for the widest range of applications. It is based on a laser melting a powder metal.
However, by 2020, as shown below, other technologies will have a foothold in the market.
Fig 1. 2020 forecast of 3D metal printer shipments by number of units.
Powder requirements and new material opportunities
Currently, the market for metal powders for 3D printing is too small to have attracted much attention for developing specific powders. In the precious metals market, suppliers have developed relationships with printer manufacturers to offer printer plus material combinations to the jewelry industry. There are some quite specific powder requirements for good quality parts. These include:
- Fine powders (usually <106 microns) allow good resolution, good surface finish and ease of melting.
- Very narrow size distribution for good consistency.
- Highly spherical powders for optimum spreading.
- Low surface area means only a small oxygen content is needed to passivate the surface, so the powder can be recycled more times and still be within the specification.
- High well-controlled purity.
For metal 3D printing to reach wide-spread adoption, there are many challenges which must still be overcome. Scale-up requires much higher reliability and repeatability of each machine and between machines and between batches of powder. The links between the materials, processing and properties are not fully understood and more research and collaboration is needed. The legal implications of customizing each item, and the testing required, are not yet clear.
For more information see the report at www.IDTechEx.com/3dmetals.