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采用套管法（ＰＩＴ）制备Ｂｉ系高温超导带材，进行了冷压工艺的优化研究。试验结果表明，Ｂｉ系带材所能承受的压力有一个限值，若超过这个限值后，密度虽可提高，但晶粒破碎严重，ＪＣ值反而降低。带材优化的冷压工艺参数是８３８℃／６０ｈ＋冷压＋８３８℃／６０ｈ＋冷压＋８３８℃／６０ｈ；第一次压力为２ＧＰａ，第二次为２．５ＧＰａ；冷压压下速率为１．７５×１０－４ｍｍ／ｓ。同时研究还表明，冷压的主要作用是提高带材的致密度和晶粒取向度，从而最终改善带材的超导性能。
Bi-based high-temperature superconducting tapes were prepared by the casing method (PIT), and the optimization of cold-pressing process was studied. The experimental results show that there is a limit to the pressure that the Bi-based strip can withstand. If the limit is exceeded, the density will increase but the grain will be broken severely and the JC value will decrease. The optimum parameters of cold-rolling process are 838 ℃ / 60h + cold pressing + 838 ℃ / 60h + cold pressing + 838 ℃ / 60h; the first pressure is 2GPa and the second is 2.5GPa; the rate of cold pressing is 1.75 × 10-4mm / s. At the same time, the research also shows that the main effect of cold pressing is to increase the density and grain orientation of the strip, and ultimately improve the superconductivity of the strip.