B i-Sr-Ca-Cu-O(BSCCO)高温超导材料在电力工程中拥有广阔的应用前景。本文全面概述了国内外研究B i系高温超导材料连接技术的现状和不足,重点介绍了BSCCO带材常规冷压成形后再高温反应退火的扩散焊连接技术,另外,阐述了近几年采用高温...B i-Sr-Ca-Cu-O(BSCCO)高温超导材料在电力工程中拥有广阔的应用前景。本文全面概述了国内外研究B i系高温超导材料连接技术的现状和不足,重点介绍了BSCCO带材常规冷压成形后再高温反应退火的扩散焊连接技术,另外,阐述了近几年采用高温加压直接扩散连接的最新研究成果。展开更多
实验表明,在烧制 Bi-Sr-Ca-Cu-O 超导体时,压片两面用银片覆盖后热处理有利于110K 超导相生成,制得的超导体有较高的零电阻温度。XPS 分析表明,在烧制超导材料时 Bi 能优先挥发,其次是 Ca。有银片覆盖可减轻 Bi 等成份的挥发程度,因此...实验表明,在烧制 Bi-Sr-Ca-Cu-O 超导体时,压片两面用银片覆盖后热处理有利于110K 超导相生成,制得的超导体有较高的零电阻温度。XPS 分析表明,在烧制超导材料时 Bi 能优先挥发,其次是 Ca。有银片覆盖可减轻 Bi 等成份的挥发程度,因此有银片覆盖的超导体中 Bi、Sr、Ca 和 O 的相对浓度比无银片覆盖的超导体中的要高。展开更多
The addition Of Pb enhances the hightemperature stability as well as theproportion of the high Tphase in Bi-Sr-Ca-Cu-O superconductor.The sample A with nominal composi-tion of BiSrCaCuOwas synthesized bySolid state re...The addition Of Pb enhances the hightemperature stability as well as theproportion of the high Tphase in Bi-Sr-Ca-Cu-O superconductor.The sample A with nominal composi-tion of BiSrCaCuOwas synthesized bySolid state reaction.It was sintered in airat 1153K for 24h,followed by annealingat 773K for 24h and furnace-cooling.The sample B with a nominal compositionof BiPbSrCaCuOwas prepared bymixing PbO with the powder ofBiSrCaCuOwhich had been prefired at1113K for 24h,pressing,sintering at展开更多
The superconducting phases with T<sub>C</sub> （0）=120-125 K and 110 K were found in the Tl-Ba-Ca-Cu-O （TBCCO） system and the Bi-Sr-Ca-Cu-O（BSCCO）system. The preparation and the prospective applicatio...The superconducting phases with T<sub>C</sub> （0）=120-125 K and 110 K were found in the Tl-Ba-Ca-Cu-O （TBCCO） system and the Bi-Sr-Ca-Cu-O（BSCCO）system. The preparation and the prospective application of TBCCO are restricted because Tl<sub>2</sub>O<sub>3</sub> is toxic, expensive and volatile. For these reasons, the BSCCO system draws more attention to some extent.展开更多
Ⅰ. INTRODUCTIONSince the discovery of oxide superconductor YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub> with transition temperature above liquid nitrogen one year ago, a tremendou...Ⅰ. INTRODUCTIONSince the discovery of oxide superconductor YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub> with transition temperature above liquid nitrogen one year ago, a tremendous amount of work has been done on oxide superconductors in thousands of laboratories in the world. It has already been shown that yttrium could be replaced by other rare-earth elements展开更多
I. INTRODUCTION The new rare-earth-free Bi-Sr-Ca-Cu-O superconducting material is possessed of higher critical temperature, stable properties and cheaper price with fine prospects. Since the new system was first repor...I. INTRODUCTION The new rare-earth-free Bi-Sr-Ca-Cu-O superconducting material is possessed of higher critical temperature, stable properties and cheaper price with fine prospects. Since the new system was first reported by H, Maeda et al. in Jan. 1988, much research works on the sys- tem has been undertaken~|2-5|. After the sharp drop of resistivity at 110 K a bulk展开更多
Recently, a discovery of new high T<sub>c</sub> oxide superconductor Bi-Sr-Ca-Cu-O has aroused special attention because of the nonexistence of rare-earth elements in it and its high T<sub>c</sub&...Recently, a discovery of new high T<sub>c</sub> oxide superconductor Bi-Sr-Ca-Cu-O has aroused special attention because of the nonexistence of rare-earth elements in it and its high T<sub>c</sub><sup>[</sup>1]. However, the preparation of high T<sub>c</sub> oxide of Bi-Sr-Ca-Cu-O was not easy. Usually, two dif ferent superconducting transitions were found, and their resistivity drops sharply around 110 K but a long tail down to even lower than liquid N<sub>2</sub> temperature was held in the展开更多
In the Bi-Sr-Ca-Cu-O superconductor system, two superconducting phases (85K and 105K) were found by Maeda et al. By substituting Pb, enhanced superconducting properties and structure stabilization in these compounds h...In the Bi-Sr-Ca-Cu-O superconductor system, two superconducting phases (85K and 105K) were found by Maeda et al. By substituting Pb, enhanced superconducting properties and structure stabilization in these compounds have been reported. Recently, the展开更多
文摘实验表明,在烧制 Bi-Sr-Ca-Cu-O 超导体时,压片两面用银片覆盖后热处理有利于110K 超导相生成,制得的超导体有较高的零电阻温度。XPS 分析表明,在烧制超导材料时 Bi 能优先挥发,其次是 Ca。有银片覆盖可减轻 Bi 等成份的挥发程度,因此有银片覆盖的超导体中 Bi、Sr、Ca 和 O 的相对浓度比无银片覆盖的超导体中的要高。
文摘The addition Of Pb enhances the hightemperature stability as well as theproportion of the high Tphase in Bi-Sr-Ca-Cu-O superconductor.The sample A with nominal composi-tion of BiSrCaCuOwas synthesized bySolid state reaction.It was sintered in airat 1153K for 24h,followed by annealingat 773K for 24h and furnace-cooling.The sample B with a nominal compositionof BiPbSrCaCuOwas prepared bymixing PbO with the powder ofBiSrCaCuOwhich had been prefired at1113K for 24h,pressing,sintering at
文摘The superconducting phases with T<sub>C</sub> （0）=120-125 K and 110 K were found in the Tl-Ba-Ca-Cu-O （TBCCO） system and the Bi-Sr-Ca-Cu-O（BSCCO）system. The preparation and the prospective application of TBCCO are restricted because Tl<sub>2</sub>O<sub>3</sub> is toxic, expensive and volatile. For these reasons, the BSCCO system draws more attention to some extent.
文摘Ⅰ. INTRODUCTIONSince the discovery of oxide superconductor YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-δ</sub> with transition temperature above liquid nitrogen one year ago, a tremendous amount of work has been done on oxide superconductors in thousands of laboratories in the world. It has already been shown that yttrium could be replaced by other rare-earth elements
文摘I. INTRODUCTION The new rare-earth-free Bi-Sr-Ca-Cu-O superconducting material is possessed of higher critical temperature, stable properties and cheaper price with fine prospects. Since the new system was first reported by H, Maeda et al. in Jan. 1988, much research works on the sys- tem has been undertaken~|2-5|. After the sharp drop of resistivity at 110 K a bulk
文摘Recently, a discovery of new high T<sub>c</sub> oxide superconductor Bi-Sr-Ca-Cu-O has aroused special attention because of the nonexistence of rare-earth elements in it and its high T<sub>c</sub><sup>[</sup>1]. However, the preparation of high T<sub>c</sub> oxide of Bi-Sr-Ca-Cu-O was not easy. Usually, two dif ferent superconducting transitions were found, and their resistivity drops sharply around 110 K but a long tail down to even lower than liquid N<sub>2</sub> temperature was held in the
文摘In the Bi-Sr-Ca-Cu-O superconductor system, two superconducting phases (85K and 105K) were found by Maeda et al. By substituting Pb, enhanced superconducting properties and structure stabilization in these compounds have been reported. Recently, the
