Renishaw, headquartered in Wotton-under-Edge, Gloucestershire, UK, recently highlighted its collaboration with Tekna Holding AS, based in Sherbrooke, Quebec, Canada. Together, the companies explored using coarse titanium powders to reduce costs and increase throughput compared to additive manufacturing with traditional fine titanium powders.
The challenge
Titanium alloys, especially Ti64, are widely used in industries such as aerospace and medical for their exceptional strength-to-weight ratio, corrosion resistance, and biocompatibility. However, the fine titanium powders (15-45 microns) used in Laser Beam Powder Bed Fusion (PBF-LB) Additive Manufacturing machines are associated with high production costs, explains Renishaw.
More broadly, the use of such fine powders can also present issues with handling. Classed as dangerous materials, airborne powders small enough to be considered dust can create health risks to operators exposed to them, requiring companies to incorporate containment systems and increased safety measures. As they are also reactive, requiring specific storage and transport considerations, their use involves costs beyond the initial investment.
Solutions
To address these issues, Renishaw reached out to Tekna to explore the use of coarse variants of titanium alloys. Tekna produces these using its radio frequency (RF) induction plasma atomisation technology, a process in which titanium wire is fed into a high-temperature plasma torch. The intense heat melts the wire, transforming it into fine droplets that solidify into spherical powder particles as they cool.
This process is said to offer advantages in sphericity, flowability and consistency. The RF induction plasma process also maintains strict control over alloying elements, reducing contamination risks.
Tekna’s proprietary plasma atomisation process is continuous and does not require any consumables that may interrupt or contaminate the process. Without any external gas jets or electrodes in contact with the material, the powder remains free from contaminants, making it well suited to demanding applications in aerospace, medical and industrial sectors.
Using this methodology, Tekna developed and optimised a large-cut variant of Ti64 powder. Renishaw worked with the company to validate the new powder, reporting the results of extensive laser parameter optimisation and powder flow testing. This workflow enabled the product to meet the performance and consistency standards required for advanced Additive Manufacturing machines.
“By combining our expertise, Tekna has developed a large-cut titanium powder that supports Renishaw’s objective of increasing overall process efficiency to their customers, while also reducing direct costs associated with the powder,” stated Amir Nobari, Technical Sales Manager, Tekna. “The coarser powder works seamlessly with Renishaw’s LPBF systems, enabling faster printing with thicker layers, while preserving essential material properties.”
Results
Through Renishaw and Tekna’s collaboration, customers can realise production cost-efficiencies that enhance the use of AM as a volume production process. This is an important step as metal PBF-LB Additive Manufacturing technology experiences greater adoption.
Additionally, coarser powders enhance overall process sustainability by increasing yield efficiency and reducing material waste. These powders also mitigate certain health and safety concerns associated with traditional AM powders, as they are not classified as dangerous goods. Fewer safety precautions during transportation lowers logistical costs and aids operational efficiency, Renishaw stated.
By utilising a thicker 90 μm or greater layer setting, users can also experience a substantial increase in build speed compared to 30 μm or 60 μm layers. This allows for improved productivity, enabling faster turnaround times.
“Renishaw’s material qualification expertise was critical in ensuring that Tekna’s large-cut titanium powder performed optimally on our systems,” stated John Laureto, Renishaw’s AM Business Manager. “Our collaboration allowed us to test rigorously and refine the material to meet the high standards required for reliable, high-quality AM.”
“The benefits of this powder extend across a variety of industries. In motorsport and automotive, it supports high mechanical strength, while making parts more lightweight. The powder is already being applied in the aerospace and defence sectors in various application areas,” he concluded.
