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本文采用初始成分为Ｔｌ＿１．８Ｃａ＿２．６Ｂａ＿２．０Ｃｕ＿３．０Ｏ＿ｙ，研究了一步合成和二步合成的短时间高温烧结及真空封闭较低温长时间热处理的Ｔｌ－２２２３制备工艺。用上述２种工艺均合成出单相性（２２２３）好的样品，其超导转变的起始温度Ｔｃ＿（ｏｎｓｅｔ）、零电阻温度Ｔｃｏ以及转变宽度△Ｔｃ分别为：一步合成样品Ｔｃ＿（ｏｎｓｅｔ）＝１３５Ｋ，Ｔｃｏ＝１２７．５Ｋ，△Ｔｃ＝５．０Ｋ，二步合成样品Ｔｃ＿（ｏｎｓｅｔ）＝１４０Ｋ，Ｔｃ。＝１２８．７Ｋ，△Ｔｃ＝７．５Ｋ。从制备工艺方面对提高Ｔｌ－２２２３的Ｔｃ进行了讨论
In this paper, the initial composition of Tl_1.8Ca_2.6Ba_2.0Cu_3.0O_y, the one-step synthesis and two-step synthesis of short-time high-temperature sintering and vacuum sealing for a long time low temperature Tl-2223 preparation process. The single-phase (2223) samples were synthesized by the above two methods. The onset temperature Tc_stack, the zero-resistance temperature Tco and the transition width ΔTc of the superconducting transitions were: Tc-onset = 135K, Tco = 127.5K, ΔTc = 5.0K, two-step synthesis sample Tc_light onset = 140K, Tc. = 128.7K, ΔTc = 7.5K. The Tc of improving Tl-2223 was discussed in terms of preparation process