A 31 page presentation by Superpower Inc at the Applied Superconductivity Conference, Washington D.C., August 1 – 6, 2010 described the details of their plan to achieve broad commercialization of superconducting wire.
They indicate that they are at $400/kA-meter at 77K, but they are hitting the $100/kA-meter price at the temperature of 30 Kelvin.
The price targets at operating field and temperature are
* < $ 100/kA-m* For commercial market entry (small market)
* < $50/kA-m* For medium commercial market
* < $25/kA-m* For large commercial market
Objectives of UH-SuperPower program focused on meeting wire price-performance metrics • Higher self-field critical current in 2G wire by increasing film thickness – HTS is still only 1 to 3% of 2G wire compared with 40% in 1G wire and is the only process that needs to be changed in 2G wire for high Ic. • Significantly modify in-field critical current performance of 2G wire – Maximize potential of rare-earth, dopant, nanostructure modifications to tailor in-field critical current in device operating conditions • Reduce wire cost by high efficiency, simpler processes – Silver electrodepositioninstead of sputtering – Substrate planarization instead of electropolishing+ buffer – Improved MOCVD precursor conversion efficiency (only 15% now) • Reduce wire cost by increased yield – Develop new and enhanced on-line QA/QC tools • Added value to customer with advanced wire architectures – Multifilamentarywire for low ac loss
• Systematic study of improved pinning by Zraddition in MOCVD films at UH.
• Two-fold improvement in in-field performance achieved !
• Zr-doped production wires with new composition exhibit significantly improved critical current at 4.2 K in high magnetic fields up to 30 Telsa
Goals for wire performance improvements
• Two-fold improvement in in-field performance achieved with Zr-doped wires
• Further improvement in Icat B || c : Now 30% retention of 77 K, zero field value at 77 K, 1 T ; Goal is 50%.
• Improvement in minimum Iccontrolling factor for most coil performance : Now 15 to 20% retention of 77 K, zero field value at 77 K, 1 T ; Goal is first 30% and then 50%
• Together with a zero-field Icof 400 A/4 mm at 77 K, self field 200 A/4 mm at 77 K, 1 T in all field orientations.
• Achieve improved performance levels at lower temperatures too (< 65 K)
• Exploring other pathways to improve in-field performance : alternate dopants
• Exploring new pathways to improve in-field performance : directed assembly
• One approach is to direct the nucleation of self-assembled nanorods from pre-deposited nucleation sites on the LMO buffer surface
• Ag (silver) in 2G wire is a limiting factor in production capacity and wire cost
• Electrodepositionis a lower-cost alternative to vacuum sputtering now used
Manufacturing of long-length, high current wires at high throughput • Increase self-field performance of production 2G wires by 25% • Increase in-field performance of Zr-doped AP wires by additional 25% • Increase production capacity and throughput by 50 - 75% • Decrease cost by 20 - 30% – Double volume of 500+ continuous meter wires • Improved pinning for enhanced high-field performance