TY - JOUR
T1 - Dispersion-strengthened silver alumina for sheathing Bi 2Sr 2CaCu 2O 8+x multifilamentary wire
AU - Kajbafvala, Amir
AU - Nachtrab, William
AU - Lu, Xi Feng
AU - Hunte, Frank
AU - Liu, Xiaotao
AU - Cheggour, Najib
AU - Wong, Terence
AU - Schwartz, Justin
N1 - Funding Information:
Manuscript received August 25, 2011; revised October 6, 2011 and November 30, 2011; accepted November 30, 2011. Date of publication January 23, 2012; date of current version February 3, 2012. This work was supported in part by the U.S. DoE Office of High Energy Physics STTR Phase I Grant DE-SC0004268. This paper was recommended by Associate Editor D. van der Laan.
PY - 2012/2
Y1 - 2012/2
N2 - High-strength high-elastic-modulus dispersion-strengthened (DS) silver aluminum alloys are studied for sheathing Bi 2Sr 2CaCu 2O 8+x (Bi2212) round wire. DS is an effective method for producing a fine grain metallurgical structure that is resistant to softening during high-temperature heat treatment. Here, DS Ag/0.5-wt.% Al (AgAl) alloy sheet is produced using powder metallurgy and is compared with Ag/0.2-wt.% Mg (AgMg) alloy, which is currently the most common alloy used for Bi2212 wire. Room temperature (RT), 77- and 4.0-K tensile tests, Vickers microhardness, optical microscopy, field emission scanning electron microscopy, and electrical resistivity measurements are compared. Furthermore, Bi2212/AgMg and Bi2212/AgAl wires are produced and compared for short-sample and coil I c (4.2 K; self-field). It is found that the AgAl solid wire shows high yield stress and ultimate tensile strength in the annealed condition at both RT and 4.0 K, as well as significant ductility at 4.0 K. Electrical transport measurements show that the Bi2212/AgAl wires perform as well or better than Bi2212/AgMg wires. Furthermore, no leakage is observed after partial melt processing (PMP) of Bi2212/AgAl spirals. After PMP, the Bi2212/AgAl wire not only has yield and tensile stresses slightly higher than those of the Bi2212/AgMg wire but also exhibits > 2% elongation, which is several times higher than that of Bi2212/AgMg.
AB - High-strength high-elastic-modulus dispersion-strengthened (DS) silver aluminum alloys are studied for sheathing Bi 2Sr 2CaCu 2O 8+x (Bi2212) round wire. DS is an effective method for producing a fine grain metallurgical structure that is resistant to softening during high-temperature heat treatment. Here, DS Ag/0.5-wt.% Al (AgAl) alloy sheet is produced using powder metallurgy and is compared with Ag/0.2-wt.% Mg (AgMg) alloy, which is currently the most common alloy used for Bi2212 wire. Room temperature (RT), 77- and 4.0-K tensile tests, Vickers microhardness, optical microscopy, field emission scanning electron microscopy, and electrical resistivity measurements are compared. Furthermore, Bi2212/AgMg and Bi2212/AgAl wires are produced and compared for short-sample and coil I c (4.2 K; self-field). It is found that the AgAl solid wire shows high yield stress and ultimate tensile strength in the annealed condition at both RT and 4.0 K, as well as significant ductility at 4.0 K. Electrical transport measurements show that the Bi2212/AgAl wires perform as well or better than Bi2212/AgMg wires. Furthermore, no leakage is observed after partial melt processing (PMP) of Bi2212/AgAl spirals. After PMP, the Bi2212/AgAl wire not only has yield and tensile stresses slightly higher than those of the Bi2212/AgMg wire but also exhibits > 2% elongation, which is several times higher than that of Bi2212/AgMg.
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U2 - 10.1109/TASC.2011.2179296
DO - 10.1109/TASC.2011.2179296
M3 - Article
AN - SCOPUS:84862805285
SN - 1051-8223
VL - 22
JO - IEEE Transactions on Applied Superconductivity
JF - IEEE Transactions on Applied Superconductivity
IS - 1
M1 - 6135777
ER -