American Superconductor Corporation has announced that it has successfully produced the world's first 20-meter-long strips of 4-centimeter (cm) wide second generation (2G) high temperature superconductor (HTS) material in a continuous reel-to-reel manufacturing process. Previously, only 1-cm wide strips had been produced in long lengths. Several 4-cm wide strips, each about 20-meters long, were produced in AMSC's pre-pilot 2G manufacturing line and were then slit in a reel-to-reel operation to produce 20-meter-long, laminated, 0.44-cm wide tape-shaped wires -- industry standard dimensions for commercial HTS wire.
Each of the laminated, individual 0.44-cm wide 2G HTS wires conducted from 60 to 70 Amperes of electrical current end-to-end when cooled with liquid nitrogen, the coolant of choice for applications such as power transmission cables. This is approximately 75 times the current that can be carried by copper wire of the same size -- a significant achievement at this stage of the manufacturing scale-up of 2G HTS wire.
AMSC's 2G HTS wire has been developed as a drop-in replacement for its commercial, first generation (1G) HTS wire, today's workhorse for the emerging HTS industry. The company's 1G HTS wire has the same width and thickness as the new 2G wire, is produced in 1,000 meter lengths and transmits more than 140 times the electrical current of copper wire of the same size, but must be produced one wire at a time.
AMSC expects the electrical current of its 2G HTS wire will exceed that of its first generation wire as 2G R&D results are implemented in its manufacturing line. A primary objective of 2G HTS wire is to achieve manufacturing costs that are 2 to 5 times lower than 1G HTS wire manufacturing costs.
"AMSC's capability to produce 4-cm wide strips of uniform, high quality 2G HTS material in one manufacturing operation, and then to slit the material into multiple narrow tape-shaped wires in the last step of production, is vital to achieving the production of 2G HTS wire at 2 to 5 times lower cost than currently achieved with today's 1G HTS wire," said Greg Yurek, chief executive officer. "The results reported today are important because they provide the first validation of AMSC's proprietary '4-centimeter manufacturing technology.' This full-process demonstration in the start-up of our new 2G HTS wire pre-pilot operation is ahead of where we expected to be at this stage. We are very encouraged because the first wires out of the gate validated our key manufacturing assumptions."
AMSC's 2G HTS Wire Status and Outlook
Today, AMSC's 2G HTS wire manufacturing technology yields 20-meter-long, 4-cm wide strips of superconductor material that are produced in a high-speed, continuous reel-to-reel deposition process -- a process that is similar to the low-cost production of motion picture film in which celluloid strips are coated with a liquid emulsion -- and subsequently slit and laminated into eight, industry-standard 0.44-cm-wide tape-shaped wires. The wires are laminated on both sides with copper or other metals to provide strength, durability and certain electrical characteristics needed in applications. AMSC expects to continue to increase the electrical performance of its 2G wire to levels that exceed the performance of it first generation HTS wire. AMSC also expects to scale up the 4-cm technology to 100-meter lengths by the end of 2005 and to 1,000 meter lengths within the next two years. The next step in the plan is to migrate to 10-cm technology to further reduce manufacturing costs. AMSC reaffirmed its plans to start shipping increased amounts of 2G HTS wire to customers from its pre-pilot line starting in the second half of calendar year 2005.
To learn more about AMSC's 2G Wire technology, please see http://www.amsuper.com/products/htsWire/2GWireTechnology.cfm.