A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the n...A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the next generation of fusion devices.Due to their high in-field transport current capacity,rare-Earth barium copper oxide(REBCO)coated conductors are promising materials for manufacturing of cable-in-conduit conductors(CICCs)for fusion.However,the high-aspect-ratio geometry makes it difficult to find a multi-tape CICC configuration that fulfills the high engineering current density requirements while retaining enough flexibility for winding large-scale magnets.Moreover,the multilayer structure and inherent brittleness make the REBCO tapes susceptible to degradation during CICC manufacturing and operation.For more than a decade,the development of a reliable REBCO-based CICC that can sustain the huge combined mechanical,thermal,and Lorentz loads without degradation has been ongoing,albeit with limited progress.In this paper,we report on a prototype REBCO CICC that can withstand an applied cyclic Lorentz load of at least 830 kN·m^(-1),corresponding to a transport current of 80 kA at 10.85 T and 4.5 K.To our knowledge,this is the highest load achieved to date.The CICC uses 288 tapes wound into six strengthened sub-cables,making it capable of having a current sharing temperature,Tcs,of around 39 and 20 K when operated under 10.85 T with a current of 40 and 80 kA,respectively.Scaled to a 20-T peak field and 46.5-kA transport current,this provides a temperature margin of over 10 K with respect to an operating temperature of 4.5 K.In addition,no perceptible transport current performance degradation was observed after cyclic Lorentz loading,cyclic warm-up/cool-down(WUCD),and quench campaigns.The proposed REBCO CICC is a milestone in the development of high-temperature superconductors for large-scale and high-field magnet applications.展开更多
基金supported by the Comprehensive Research Facility for the Fusion Technology Program of China(2018-000052-73-01-001228)the National Key Research and Development Program of China(2022YFE03150200)+3 种基金the Institute of Energy,Hefei Comprehensive National Science Center(21KZS207)the National Natural Science Foundation of China(52077212)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2021444)the European–China collaboration program on the FUSION magnet.
文摘A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the next generation of fusion devices.Due to their high in-field transport current capacity,rare-Earth barium copper oxide(REBCO)coated conductors are promising materials for manufacturing of cable-in-conduit conductors(CICCs)for fusion.However,the high-aspect-ratio geometry makes it difficult to find a multi-tape CICC configuration that fulfills the high engineering current density requirements while retaining enough flexibility for winding large-scale magnets.Moreover,the multilayer structure and inherent brittleness make the REBCO tapes susceptible to degradation during CICC manufacturing and operation.For more than a decade,the development of a reliable REBCO-based CICC that can sustain the huge combined mechanical,thermal,and Lorentz loads without degradation has been ongoing,albeit with limited progress.In this paper,we report on a prototype REBCO CICC that can withstand an applied cyclic Lorentz load of at least 830 kN·m^(-1),corresponding to a transport current of 80 kA at 10.85 T and 4.5 K.To our knowledge,this is the highest load achieved to date.The CICC uses 288 tapes wound into six strengthened sub-cables,making it capable of having a current sharing temperature,Tcs,of around 39 and 20 K when operated under 10.85 T with a current of 40 and 80 kA,respectively.Scaled to a 20-T peak field and 46.5-kA transport current,this provides a temperature margin of over 10 K with respect to an operating temperature of 4.5 K.In addition,no perceptible transport current performance degradation was observed after cyclic Lorentz loading,cyclic warm-up/cool-down(WUCD),and quench campaigns.The proposed REBCO CICC is a milestone in the development of high-temperature superconductors for large-scale and high-field magnet applications.
