A major ship builder has acquired a vacuum furnace for the Additive Manufacturing Division at the company’s new Manufacturing Center of Excellence. The single chamber vacuum furnace will be used primarily for annealing powder metal 3D printed parts, with additional capabilities for on-demand tool hardening applications.
Piotr Zawistowski Managing Director SECO/VACUUM Source: SECO/VACUUM
The 3D printing shop and annealing furnace supplied by SECO/VACUUM will enable rapid fabrication of critical replacement parts faster than traditional manufacturing methods, allowing the manufacturer to get ships out of dock and back underway sooner. The Vector furnace is equipped with a 36 x 36 x 48 inch metal hot-zone, a high-vacuum diffusion pump, and a 6-Bar high-pressure argon and nitrogen gas quench.
“To get their 3D operation up and running quickly, we were able to pull off some clever production schedule juggling in order to accommodate their special request for an accelerated delivery schedule,” said Piotr Zawistowski, managing director of SECO/VACUUM.
This vacuum furnace provides a wide range of additional processes, including hardening, tempering, solution heat treating, brazing and sintering, and low-pressure carburizing. Vector produces clean, uniform, high-quality parts with repeatable accuracy and no oxidation.
The press release is available in its original form here.
Scientists at several research institutions recently reported a breakthrough in 3D printing a marine grade stainless steel — a low-carbon type called 316L — that promises high-strength and high-ductility properties. Researchers at Lawrence Livermore National Laboratory (LLNL), along with collaborators at Ames National Laboratory, Georgia Tech University, and Oregon State University, published their findings online October 30, 2017, in the journal Nature Materials.
LLNL scientist Morris Wang (left) and postdoc researcher Thomas Voisin played key roles in a collaboration that successfully 3D printed one of the most common forms of marine grade stainless steel that promises to break through the strength-ductility tradeoff barrier.
“Marine grade” stainless steel is valued for its performance under corrosive environments and for its high ductility — the ability to bend without breaking under stress — making it a preferred choice for oil pipelines, welding, kitchen utensils, chemical equipment, medical implants, engine parts and nuclear waste storage. However, conventional techniques for strengthening this class of stainless steels typically comes at the expense of ductility.
“In order to make all the components you’re trying to print useful, you need to have this material property at least the same as those made by traditional metallurgy,” said LLNL materials scientist and lead author Morris Wang. “We were able to 3D print real components in the lab with 316L stainless steel, and the material’s performance was actually better than those made with the traditional approach. That’s really a big jump. It makes additive manufacturing very attractive and fills a major gap.”
Wang said the methodology could open the floodgates to widespread 3D printing of such stainless steel components, particularly in the aerospace, automotive, and oil and gas industries, where strong and tough materials are needed to tolerate extreme force in harsh environments.
To successfully meet, and exceed, the necessary performance requirements for 316L stainless steel, researchers first had to overcome the porosity which causes parts to degrade and fracture easily during the laser melting (or fusion) of metal powders. Researchers addressed this through a density optimization process involving experiments and computer modeling, and by manipulating the materials’ underlying microstructure.
Researchers say the ability to 3D print marine grade, low-carbon stainless steel (316L) could have widespread implications for industries such as aerospace, automotive, and oil and gas.
“This microstructure we developed breaks the traditional strength-ductility tradeoff barrier,” Wang said. “For steel, you want to make it stronger, but you lose ductility essentially; you can’t have both. But with 3D printing, we’re able to move this boundary beyond the current tradeoff.”
Using two different laser powder bed fusion machines, researchers printed thin plates of stainless steel 316L for mechanical testing. The laser melting technique inherently resulted in hierarchical cell-like structures that could be tuned to alter the mechanical properties, researchers said.
Wang called stainless steel a “surrogate material” system that could be used for other types of metals. The eventual goal, he said, is to use high-performance computing to validate and predict future performance of stainless steel, using models to control the underlying microstructure and discover how to make high-performance steels, including the corrosion-resistance. Researchers will then look at employing a similar strategy with other lighter weight alloys that are more brittle and prone to cracking.
“We didn’t set out to make something better than traditional manufacturing; it just worked out that way,” said LLNL scientist Alex Hamza, who oversaw production of some additively manufactured components.
Lightweight metals leader Alcoa (NYSE:AA) has entered into an agreement with Airbus to supply 3D-printed titanium fuselage and engine pylon components for Airbus commercial aircraft. Alcoa expects to deliver the first additive manufactured parts to Airbus in mid-2016.
“We are proud to partner with Airbus to help pave the way to the future of aerospace development and manufacturing,” said Alcoa Chairman and Chief Executive Officer Klaus Kleinfeld. “The unique combination of our multi-material alloy development expertise, powder production capabilities, aerospace manufacturing strength and product qualification know-how position us to lead in this exciting, emerging space.”
Airbus chose to work with Alcoa because of its comprehensive capabilities, from materials science leadership to additive manufacturing and aerospace parts qualification. The agreement will draw on Alcoa’s decades of aerospace experience and new technologies gained through the recent acquisition of RTI and organic expansion in Whitehall, Michigan. Alcoa also recently invested in 3D-printing and metallic powder production capabilities at its technical center outside of Pittsburgh, Pennsylvania.
Last year, Alcoa acquired RTI International Metals (RTI)—now known as Alcoa Titanium & Engineered Products (ATEP)—which grew Alcoa’s additive manufacturing capabilities to include 3D-printed titanium and specialty metals parts produced at ATEP’s Austin, Texas facility. The Airbus agreement will draw on these capabilities as well as ATEP’s titanium ingot melting and billetizing, machining, finishing and inspection technologies.
Alcoa will employ advanced CT scan and hot isostatic pressing (HIP) capabilities at its advanced aerospace facility in Whitehall, Michigan. HIP is a technology that strengthens the metallic structures of traditional and additive manufactured parts made of titanium and nickel based superalloys. Through a $22 million investment in the technology in Whitehall, Michigan, Alcoa today owns and operates one of the largest aerospace HIP technology complexes in the world.
Additionally, Alcoa is bolstering its additive manufacturing capabilities through a $60 million expansion in advanced 3D-printing materials and processes, including metallic powders. The expansion is located at the Alcoa Technical Center near Pittsburgh, Pennsylvania, the world’s largest light metals research center.
