Mike Adams, CEO at HiETA Technologies, is a staunch advocate for additive manufacturing but states that as the technology evolves, so must the raw materials which will be transformed into the goods of the future.
“You can print whatever you want”. Start talking about additive manufacturing or 3D printing and that’s what you’re likely to hear. However, this is not yet the case. One of the main reasons? Materials. Materials are everything to the engineer. In 3D printing this is especially true, where the material choice can be crucial to the success of the build. As such, the development of these manufacturing technologies is directly linked to materials development. As the capability matures from simply prototyping, the ability to process an increasing catalogue of materials into an end product is coming to the fore.
The world of 3D printing started with polymers, specifically photo-reactive polymers, with stereolithography as the first process to be commercialised. This process and material combination can be considered the parents of the additive manufacturing industry. It is also, arguably, one of the most understood particularly in terms of resulting material properties. Manufacturing giants such as Siemens have used stereolithography in the production of customised hearing aids, one of the first applications of additive manufacturing which can be considered true “production”.
“The successful uptake of production in this field is highly dependent on the development and adaptation of both current and new materials”
Powder materials make up a large amount of additive manufacturing raw materials. Very fine powders are combined with tools such as lasers or electron beams to create functional parts in both metals and polymers. The quality of these powders has a significant effect on the material microstructure and final component properties. However, thanks to the Technology Strategy Board’s recent funding in this area, a number of UK projects such as the 3T RPD led ANVIL project, and the HIETA led HiEND project, the challenges are being tackled.
The majority of additive manufacturing metals’ development has been led by the medical and aerospace fields and used in the production of high performance and complex structures. Significant applications in the development of additive manufacturing include dental implants, bone replacements and lightweight aircraft components. This has resulted in many materials such as titanium alloys, maraging steels, Stainless 316 and cobalt chrome becoming available for commercial use when combined with laser or electron beam processing.
In an industry growing as rapidly as this, what first seems impossible or improbable, often becomes reality. When HiETA initially started, we were told that aluminium alloys could not be processed through a laser process for a number of technical reasons, and that it was not going to happen anytime soon. 12 months later and aluminium was being processed and now has the potential to become a large part of the burgeoning metals additive manufacturing industry.
Another exciting area of potential is the possibility of additive manufacturing high performance ceramics. Soon it may be possible to have greater manufacturing control over the properties of ceramic components, combined with highly complex design not possible through current powder forming or machining processes.