Effects of silver additions on resistance to thermal shock and delayed failure of YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] superconductors

Journal Article · Tue Jun 01 04:00:00 EDT 1993 · Journal of Materials Research; (United States)

DOI:https://doi.org/10.1557/JMR.1993.1226· OSTI ID:6212022

Singh, J P; Joo, J; Singh, D; Warzynski, T; Poeppel, R B ^[1]

---

1. Materials and Components Technology Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

The effect of silver (Ag) addition on the resistance to thermal shock and delayed failure of YBa[sub 2]Cu[sub 3]O[sub 7[minus][delta]] superconducting wires has been evaluated. Resistance to thermal shock was evaluated by measuring critical-current density ([ital J][sub [ital c]]) as a function of the number of thermal cycles for YBCO and its composites with 15 vol.% Ag additions. Composite YBCO-Ag wires show a slower decrease in [ital J][sub [ital c]] than does monolithic YBCO as the number of thermal cycles increases. The nature of delayed failure was studied by measuring strength ([sigma][sub [ital f]]) as a function of loading rate ([dot [sigma]]) and evaluating the value of the subcritical crack growth parameter [ital N] [[sigma][sub [ital f]]=[ital A][dot [sigma]][sup 1/([ital N]+1)]]. The value of [ital N] parameter was observed to increase slightly from 35 for YBCO to 41 for YBCO-Ag composites. The improved resistance to thermal shock and subcritical crack growth is believed to be due to improvements in mechanical properties (strength and fracture toughness) and thermal conductivity of YBCO as a result of Ag addition.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6212022
• Journal Information: Journal of Materials Research; (United States), Journal Name: Journal of Materials Research; (United States) Vol. 8:6; ISSN JMREEE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CRITICAL CURRENT
CURRENTS
ELECTRIC CURRENTS
FAILURES
HIGH-TC SUPERCONDUCTORS
MATERIALS TESTING
MECHANICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
SILVER ADDITIONS
SILVER ALLOYS
SUPERCONDUCTORS
TESTING
THERMAL SHOCK
TRANSITION ELEMENT COMPOUNDS
WIRES
YTTRIUM COMPOUNDS
YTTRIUM OXIDES