Internal friction and elastic softening in polycrystalline Nb/sub 3/Sn

Journal Article · Thu Oct 01 04:00:00 EDT 1981 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.24.4087· OSTI ID:5978198

Bussiere, J F; Faucher, B; Snead, Jr, C L; Welch, D O

The vibrating-reed technique was used to measure internal friction and Young's modulus of polycrystalline Nb/sub 3/Sn in the form of composite Nb/Nb/sub 3/Sn tapes from 6 to 300 K. In tapes with only small residual strain in the A15 layers, a dramatic increase in internal friction with decreasing temperature is observed with an abrupt onset at approx.48 K. The internal friction Q/sup -1/ between 6 and 48 K is believed to be associated with stress-induced motion of martensitic-domain walls. In this temperature range, Q/sup -1/ is approximately proportional to the square of the tetragonal strain of the martensitic phase; Q/sup -1/..cap alpha.. (c/a-1)/sup 2/. With residual compressive strains of approx.0.2%, the internal friction associated with domain-wall motion is considerably reduced. This is attributed to a biasing of domain-wall orientation with residual stress, which reduces wall motion induced by the (much smaller) applied stress. The transformation temperature, however, is unchanged (within +- 1 K) by residual strains of up to 0.2%. Young's modulus exhibits substantial softening on cooling from 300 to 6 K. This softening, is substantially reduced in the presence of small residual compressive strains, indicating a highly nonlinear stress-strain relationship as previously reported for V/sub 3/Si.

• Research Organization: Institut de genie des materiaux, CNRC, 750 Bel-Air, Montreal, Canada H4C 2K3
• OSTI ID: 5978198
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 24:7; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
360104 -- Metals & Alloys-- Physical Properties
ALLOYS
CARBON ADDITIONS
CRYSTAL-PHASE TRANSFORMATIONS
CRYSTALS
DATA
DOMAIN STRUCTURE
EXPERIMENTAL DATA
FRICTION
INFORMATION
INTERNAL FRICTION
IRON ALLOYS
LOW TEMPERATURE
MARTENSITE
MECHANICAL PROPERTIES
MEDIUM TEMPERATURE
NIOBIUM ALLOYS
NUMERICAL DATA
PHASE TRANSFORMATIONS
POLYCRYSTALS
TEMPERATURE DEPENDENCE
TIN ALLOYS
ULTRALOW TEMPERATURE
VERY LOW TEMPERATURE
YOUNG MODULUS