Linde's Pioneering Gas Blends for Additive Manufacturing
Based on Materials Science expertise, Linde brings bespoke gas blends like its ADDvance® Laser230 to the additive manufacturing process - with real benefits for customers.
Linde Launches Additive Manufacturing into a New Realm
Linde's ADDvance® Laser230 bespoke gas blend was developed specifically for PBF-LB manufacturers looking for consistent results.
Materials scientists and engineers at Linde have dedicated the past few years to developing pioneering solutions for additive manufacturing (AM) - a process increasingly employed in the development of spare parts, small series production and tooling in forward thinking manufacturing industries such as aerospace, electronics, automotive and medical devices. A deep knowledge of materials science has allowed engineers to understand the impact of the printing chamber's atmosphere on the printed part, highlighting the key role of gases in achieving optimal conditions.
"We have developed unique and bespoke gas mixtures that offer proven benefits when working with certain alloys for specific applications," explains Pierre Forêt, Associate Director, Additive Manufacturing, Linde. ADDvance® Laser230 is one such proprietary blend of argon and helium developed specifically to take Powder Bed Fusion with Laser Beam (PBF-LB) reliability and reproducibility to the next level. ADDvance® Laser230 minimizes the possibility of internal defects and helps to mitigate fumes and spatter formation - thus enhancing quality and productivity. It can also accelerate cycle times, making the printing process more reliable and lowering the cost per part. Also, being alloy agnostic makes this an ideal solution for additive manufacturing of complex or lattice-type structures (like those pictured above). "It's a major step forward," explains Forêt.
Materials Science and the Art of the Possible
Innovative materials play an essential role in modern life. From heart stents to spacecraft components, the structure, composition, properties, and performance of materials are put to the test in extreme environments. The fact that such products pass these tests is thanks to advances in materials science and engineering, which have enabled a deeper understanding of how materials - everything from metals and polymers to composites and nanomaterials - behave at every level, including how a structure can be engineered to achieve better performance. As a result, this interdisciplinary field has advanced not only product design but also manufacturing – with a recent focus on additive manufacturing.
By fusing together metal powders layer by layer, using a number of different sintering or laser-based techniques, additive manufacturing can build complex components that would typically be very challenging - if not impossible - with more traditional subtractive manufacturing methods. "While additive manufacturing offers a host of benefits like greater design freedom and improved product strength and functionality, the industry has faced a challenge in retaining or even improving the characteristics of the metal alloys typically used in the process," Forêt explains. Again, Linde leans on its materials science and gases expertise to find a solution.
Sending Complex Components into Space
In 2023, Linde announced a collaboration with Ariane Group in a research project to help improve the additive manufacturing process of copper alloy parts to be used in engine combustion chambers of future heavy-lift rockets. Space might well be the ultimate testing ground for materials. Every single component of a spacecraft will be put under severe stress. To overcome the earth's gravitational pull at launch, spacecraft will experience up to three times the force of Earth's gravity. Not to mention some serious vibrations. Once in orbit, satellites will experience temperature shifts as they move into sunlight or behind the earth's shadow. Spacecraft re-entering can experience temperature spikes of up to 2,760 degrees Celsius due to the friction of the atmosphere at such high speeds. Add to the mix increased radiation exposure and impacts with space junk and it soon becomes obvious that only the strongest materials will survive.
With the advancement of additive manufacturing, copper powder can now be used to develop engine components with highly specialized geometries (such as cooling channels), which were previously impossible using traditional manufacturing methods. While a superior heat conductor and recognized as a vital material for the aerospace industry, copper faces challenges in relation to the additive manufacturing process due to its reflective properties. As Forêt explains: "The copper acts like a mirror to the laser so that a considerable amount of power is reflected and not used to melt the metal." A higher laser intensity is therefore needed, but this can risk overheating of the part and oxidation issues.
Propelling Additive Manufacturing Innovation Skyward
Using its bespoke gas mixture ADDvance® Laser230, along with its unique oxygen control system, ADDvance® O2 precision, Linde is collaborating with Ariane to test a highly precise additive manufacturing process to deliver consistent, high quality printed copper components (like the combustion chamber pictured). "To ensure the competitiveness of future launcher engines, improved additive manufacturing processes are a key factor, enabling reduced manufacturing costs and improved lead times while maintaining the non-negotiable quality and reliability that has made Ariane an industry leader," says Mathias Palm, Process Specialist, Ariane Group.
Whatever the application - whether Space or the more earthly Medical and Energy industries - optimized products rely on optimized processes. With the aptly named ADDvance ® solutions, Linde is ready to propel manufacturing innovation forward for its customers.