標準號：IEC 61788-2-2006
中文標準名稱：超導性.第2部分:臨界電流測量.Nb
英文標準名稱：Superconductivity - Part 2: Critical current measurement - DC critical current of Nb
標準類型：K10
發(fā)布日期：1999/12/31 12:00:00
實施日期：1999/12/31 12:00:00
中國標準分類號：K10
國際標準分類號：17.220;29.050
適用范圍：This part of IEC 61788 covers a test method for the determination of the d.c. critical current ofNb3Sn composite superconductors which are fabricated by either the bronze process or theinternal tin diffusion process and have a copper/non-copper ratio larger than 0,2.This method is intended for use with superconductors which have critical currents of less than1 000 A and n-values larger than 12 under standard test conditions and at magnetic fields ofless than or equal to 0,7 times the upper critical magnetic field. The test specimen isimmersed in a liquid helium bath at a known temperature during testing. The Nb3Sncomposite test conductor has a monolithic structure with a total round-cross-sectional areathat is less than 2 mm2. The specimen geometry used in this test method is an inductivelycoiled specimen. Deviations from this test method which are allowed for routine tests andother specific restrictions are given in this standard.Nb3Sn conductors with critical currents above 1 000 A or total cross-sectional areas greaterthan 2 mm2 can be measured with the present method with an anticipated reduction inprecision and a more significant self-field effect (see Annex C). Other, more specialized,specimen test geometries may be more appropriate for larger conductor testing which havebeen omitted from this present standard for simplicity and to retain precision.The test method given in this standard should in principle apply to Nb3Sn composite wiresfabricated by any other process. This method is also expected to apply to othersuperconducting composite wires after some appropriate modifications.