This week at the lab, we're trying a magnet on for size.
A research magnet is made of a set of coils engineered from a current-carrying material — a fancy version of the electromagnet many kids make in school using a wire, battery and nail. Typically, four or five coils are slid one inside the next like Russian nesting dolls.
This week, we're slipping the second coil of the highly anticipated 32 tesla all superconducting magnet over the inner-most coil, then making any necessary adjustments. Like a good pair of jeans, the fit should be snug but not tight, with a mere millimeter between the two coils.
"Assembling the coils and the entire electrical circuit is an intricate job, and an exiting one," said project leader Huub Weijers. "After almost seven years of development, design, testing and construction of components, the final magnet is taking shape in front of our eyes."
These two coils, which contain about 6 miles of superconducting tape made of the novel, high-temperature superconductor yttrium barium copper oxide (YBCO). But YBCO is only one layer in this magnet. Those coils will soon be nested inside five more of coils made of conventional superconductors, three of niobium-tin and two of niobium-titanium.
The finished, 2.3-ton magnet system, when completed this summer, will join the MagLab’s roster of world-record magnets. At 32 tesla, it will be by far the strongest superconducting user magnet in the world, surpassing the current record of 23.5 tesla.
"It’s a difficult task to work through the many details of a new technology," said the magnet's lead designer Adam Voran, who managed the computer modeling for the project. "But the reward of seeing those meticulous designs being born into a tangible reality is exhilarating."
Photo by Stephen Bilenky / Text by Kristen Coyne.
This week at the lab, Peng Chen starts a new job at the Applied Superconductivity Center (ASC), where he will contribute to developing a groundbreaking magnet with bismuth-strontium-calcium-copper-oxide (Bi-2212), a promising high-temperature superconductor.
Chen's new job sounds a lot like his old job: building a groundbreaking magnet at the ASC with Bi-2212. The main difference is that last week, Chen was still a graduate research assistant. This week, he is a postdoctoral research associate, having graduated Saturday from Florida State University (FSU) with a Ph.D. in mechanical engineering.
"I can relax a little bit," laughed Chen, who has put in long hours over the past several months writing and revising his thesis.
In addition to designing and building world-record magnets used by scientists from across the globe, the MagLab has an important educational mission. This includes training early-career scientists like Chen. It's not by accident that undergraduates, graduate students and postdocs make up 40 percent of the lab's staff.
Since arriving here from China five years ago, Chen has experienced an intense, hands-on education among the team building a Bi-2212-based, high-field, high-homogeneity nuclear magnetic resonance magnet dubbed the Platypus. ASC Director David Larbalestier, who is Chen's advisor, said Chen has shown a lot of grit in the face of tough technical problems that come with building a first-of-its-kind instrument. In fact, ASC is hoping to get a patent out of a fully superconducting joint Chen built for the Platypus.
"He combines an engineering viewpoint with a strong desire to understand what he is doing, which makes his approach to complex technical problems very valuable," said Larbalestier, who placed the blue doctoral hood on Chen during his graduation ceremony to signify his former student’s new status.
Chen said he is looking forward to his new role on the team.
"In the transition from student to postdoc, you have more freedom," said Chen. "It's not only about your dissertation; you have more choices to do different aspects of the project and to collaborate with other teammates to support them — take more responsibility. I have a feeling I will do more and broaden my duties."
Text by Kristen Coyne / Photo courtesy of Peng Chen.
Using a novel method of winding the magnet coil that dispensed with the traditional insulation, the MagLab reached another world record and laid the foundation for more to come.
No insulation? No problem! In fact, by challenging the conventions of magnet making, MagLab engineers created a first-of-its-kind magnet that has only just begun to make records.
This week at the lab, engineers are winding a coil for a new, hybrid magnet system that will match the field strength of our own world-record magnet.
Two teams from two magnet labs located on two continents have joined forces on this project.
The High Field Magnet Lab (HFML), located in Nijmegen, the Netherlands, is building a continuous-field magnet designed to generate a field of 45 tesla, which will tie the record now held by the MagLab’s 45 tesla hybrid magnet. The National MagLab is lending its expertise to the effort by building the superconducting portion of the magnet; the HFML is building the resistive portion.
In the end, five spools of cables containing a total of 2 km of superconducting wire will be joined and wound to form a 5-ton coil. The winding process alone requires several months. “Electrically you have to continue that path from one length of conductor to the next,” said MagLab engineer Iain Dixon, who is heading up the project. “There’s a lot of care and a lot of checks that go on to make sure that the bends are in the right place and the cuts are in the right place."
The inter-lab collaboration has meant a lot of back and forth for both teams. Andries den Ouden, head of superconducting magnet technology at Nijmegen, was in Tallahassee recently.
"During the project operation, there are no walls between the two labs," said den Ouden. "There's an open exchange of information … I think that's one of the key benefits."
Text by Kristen Coyne / Photo by Stephen Bilenky.
A new type of superconducting cable was successfully tested at high field at the MagLab, opening the door for the next generation of accelerator magnets operating at 20 teslas (T) and above.
New calculations that reveal the workings of a new type of high-field research magnet will aid in future magnet designs.
This week at the lab started for Safety Director Kyle Orth the same way it does every Monday: a powwow with the engineers and technicians building the lab's 36-tesla series connected hybrid magnet.
"Every Monday morning we go through the work that's going be done during the week, so we can identify the hazards that would be associated with that work and what needs to be done to mitigate those hazards."
This week that work includes removing some of the 5,000-lb. iron scaffolding used during the construction of the system that is no longer needed. Because this work involves clambering 20 feet above a concrete floor, workers must wear fall protection, hard hats and safety glasses. In addition, workers who will be inside the bore of the magnet will take precautions associated with being in a confined space, including carrying a multi-gas meter that sounds an alarm if the oxygen level dips too low.
The process is called integrated safety management, or ISM. Prior to any work that is potentially hazardous, MagLab employees review the situation and make plans for ensuring the job is done safely. Regular lab-wide meetings and posters hung throughout the facility also contribute to building a culture of safety at the lab.
Orth and other members of the safety department guide MagLab staff through ISM reviews about a dozen times a week, and groups like the SCH team start every day with a safety meeting. The team will continue those daily reviews until the new magnet, expected to break the record for field homogeneity for a high-field magnet, is completed early next year.
"It's the ISM process at the grassroots level, where it's actually being implemented," Orth said.
Video by Stephen Bilenky / Text by Kristen Coyne
Homogeneous magnets make data clearer for scientists. The MagLab has some of the most homogeneous magnets in the world.
Reduced-size prototype coils for the 32 T all-superconducting magnet have been successfully tested. The results include the generation of 27 T, which is a record for superconducting magnets.