Manufacturing science at Oak Ridge National Laboratory made out well in 2020, despite and in response to the COVID-19 pandemic.

That was one message of Craig Blue, manager of ORNL’s Advanced Manufacturing Program and founding director of the Manufacturing Demonstration Facility (MDF), who told the Friends of ORNL recently that the lab issued 40 news releases on ORNL manufacturing research alone in 2020.

One story receiving national attention was the interaction of ORNL manufacturing researchers with Peter Tsai, the retired professor from the University of Tennessee who invented and patented the electrostatically charged filter media in N95 respirators. These highly protective masks were in short supply for American hospital staff treating a growing number of patients struggling to survive COVID-19. ORNL staff and Tsai, who came out of retirement, collaborated on scaling up production of the masks, making them reusable and working with industry to mass produce them, creating jobs and saving lives.

The MDF, the U.S. Department of Energy’s largest advanced manufacturing research center, is known for its co-development and use with industry of 3D printing technologies, or additive manufacturing (AM) machines, to demonstrate the fabrication of objects of all sizes and complex shapes. The technologies use a variety of materials, from polymers and carbon composites to metallic alloys.

Now in its 10th year, the MDF is, according to Blue, “No. 1 in additive manufacturing research in the country.” The medical technology, aerospace and automotive industries are leading the implementation of additive manufacturing in the United States.

AM, or 3D printing, is a process that creates a physical object from a digital model file. The AM machine adds layer upon layer of material to build up a complete object such as a car chassis, engine part or turbine blade mold. Additive manufacturing is the opposite of traditional “subtractive” processes by which material is removed (or subtracted) from a larger block to create the final object. Today’s 3D printers give the producer more control, more flexibility and greater speed in making a mold or suddenly needed part.

"In 2013 we developed a new polymer that can be 3D printed,” Blue said. “Then we co-developed two of the biggest polymer printers in the world. We started the large-scale polymer additive manufacturing industry.”

This work has benefited the local economy. For example, Techmer PM of Clinton commercialized materials for large-scale polymer AM and opened a new dedicated production line to produce polymer powders for 3D printing.

Over the years, the MDF has “printed” a robotic hand, five cars, molds for building parts, a submersible boat for the Navy, a trimming tool for Boeing 777 aircraft that achieved a Guinness World Record in 2016 as the largest 3D printed tool, and a nose cone with ablative carbon composite material for NASA that will be sent to the International Space Station later this year. Also, 3D printed stainless-steel fuel assembly parts from ORNL will be inserted in the Tennessee Valley Authority’s Browns Ferry Nuclear Plant during a 2021 refueling outage.

In 2020, MDF staff showed they can grow a single-crystal high-temperature turbine blade for fossil, hydroelectric and wind energy systems.

“In 2020 we were the first to demonstrate control of 3D microstructures,” Blue said.

Embedded in MDF are staff with Zeiss, a Minnesota company determined to become the best in applying its precision inspection and metrology expertise to verifying that 3D-printed parts are absolutely reliable. Zeiss brought $8 million worth of equipment to MDF to test its inspection techniques.  

One major ORNL technical achievement for the MDF was the recent development of Peregrine, software using artificial intelligence to assess in real time the quality of parts being produced by 3D printing without the need for expensive characterization equipment. The software is used to monitor the addition of layers of molten polymer powders fused by laser or electron beams to build a desired object. If Peregrine detects an anomaly in a layer that could degrade the properties of the part, it alerts the operator so adjustments can be made. Defects include swelling, debris, spatter and soot.

The Peregrine software is copyrighted and has been licensed to four companies — GE Additive, Raytheon Technologies, Cummins and Blue Origin (owned by Amazon founder Jeff Bezos).

"GE is the largest additive manufacturer in the world,” Blue said. “GE put up to $4 billion in AM but sees the need to work with MDF to get a fundamental understanding of the process.”

He added that ORNL has a major deal with GE to fabricate geothermal energy systems.

Since MDF’s inception in 2012, it has been involved in more than 50 university collaborations and more than 200 cooperative research and development agreements (CRADAs) with industry, which are partially funded by DOE (50% of the more than 100 advanced manufacturing systems at MDF are supplied by industry through CRADAs).

“MDF has had $1 billion in U.S. industry impact,” Blue said, explaining that after industrial partners finish their development work at MDF, they have invested a total of $1 billion in additive manufacturing systems.

“That’s a 20 to 1 return on investment of DOE funds in CRADAs at the MDF,” he added.

In 2019, MDF researchers working with Gate Precast and PCI created the first 3D molds for the white precast concrete façade of a 42-story residential and commercial tower being built in Brooklyn on the waterfront site of the former Domino Sugar Factory. The façade evokes the form of a sugar crystal.

The molds, produced on ORNL’s Big Area Additive Manufactured (BAAM) machine, are made of thermoplastic compounded with chopped carbon fibers. Unlike the conventional wood molds, the 3D-printed molds were durable enough to cast at least 200 concrete parts, a key requirement for meeting the project’s schedule. Many of the molds were later fabricated by Additive Engineering Solutions (AES) of Akron, Ohio, enabling it to increase its workforce as it experienced yearly revenue growth of 110%.

 A local startup that resulted from work at MDF is Volunteer Aerospace, which hired seven people, acquired five additive systems and fabricated flight-critical, qualified components in under three years.

MDF co-developed with MVP a large thermoset printer, and as a result MVP moved to Knoxville. (Thermoset printers work with synthetic materials that set permanently when heated whereas thermoplastic printers, also at the MDF, use synthetic materials that become plastic on heating and harden on cooling.)

Through training of some 1,300 personnel with Boeing, the Navy and other organizations, MDF is addressing the American machine tool crisis.

“The U.S. has lost 30% to 40% of its tool and die manufacturing business,” Blue said.

Personnel at MDF have demonstrated that 3D printing can be used to make machine tools and dies rapidly.

"Except for 2020, MDF has averaged 7,000 visits from 1100 companies per year,” Blue said.

MDF staff also have trained 700 college students through 1,000 internships since 2012 and worked with local high school students involved in FIRST Robotics team competitions.

   In 2018, the MDF staff moved from its initial 42,000 square-foot building to a 110,000 square-foot building; both buildings are located close to ORNL’s National Transportation Research Center on Hardin Valley Road in Knox County. In addition, ORNL created the new Manufacturing Science Division, which includes MDF and the Carbon Fiber Technology Facility. CFTF seeks to reduce the cost of producing carbon fiber for potential use in making lighter, more-energy-efficient vehicles. The division has 140 staff members.

Working with former University of Tennessee professor Tsai, the CFTF responded to American hospitals’ mass shortage of N95 masks in early 2020. Tsai helped CFTF convert its machinery from producing carbon fiber from a precursor to making filtration fabric. The process involved melt blowing a polymer resin at high air speed to create microfibers that are randomly deposited, forming a sheet of material.

Tsai helped CFTF incorporate an ORNL-invented charging system into the melt blowing line at the CFTF. In addition to doing mechanical filtering, N95 material has stationary electric charges that attract and trap more than 95% of the submicron fluid droplets found in the coronavirus.

“Then we worked with Cummins in Middle Tennessee to convert two of their melt-blown lines for making filter media for diesel engines so that they could mass produce N95 filtration material,” Blue said. “Within three months we were able to get a company in Florida to make masks using the N95 filter media produced by Cummins. They were making and selling three million masks a day.”

MDF used 3D printing to make metal molds that the Tennessee medical manufacturer DeRoyal used to make millions of face shields. MDF molds were used to mass produce plastic tubes that enclosed swabs and saline solution in kits needed to determine whether people test positive for COVID-19.  

In a news release, Lonnie Love, lead scientist for ORNL’s COVID-related advanced manufacturing initiatives, said, “We do the scientific research, overcome the challenges, and then provide industry a turnkey solution that allows them to take our tools and rapidly manufacture critical equipment to meet U.S. demand.”

Blue concluded, “We helped create 1,500 new jobs for producing the needed medical supplies to fight COVID-19.”