Effect of anodic oxide films on low temperature mechanical behavior of niobium single crystals

Conference · Fri Oct 31 04:00:00 EST 1975

OSTI ID:4114554

Sethi, V. K.; Gibala, R.

The effect of thin (less than or equal to 1500 A) anodic oxide films on the mechanical behavior of single crystals of niobium at low temperatures (T less than or equal to 0.15 T/sub M/) was investigated. Oxide films affect mechanical behavior in two ways: the yield stress is reduced and the stress-strain curves are serrated over an appreciable range of strains. When oxide-coated specimens are also prestrained into stage I at 300$sup 0$K, the serrations observed at low temperatures disappear, the flow stress is further reduced, the ductility is increased, and a three-stage work hardening behavior occurs. A model involving generation and motion of nonscrew dislocations from the oxide-metal interface is used to explain the results. (auth)

• Research Organization: Case Western Reserve Univ., Cleveland, Ohio (USA). Dept. of Metallurgy and Materials Science
• NSA Number: NSA-33-015261
• OSTI ID: 4114554
• Report Number(s): COO--1676-38; CONF-750999--1
• Country of Publication: United States
• Language: English

Related Subjects

*NIOBIUM-- MECHANICAL PROPERTIES
360103* --Materials--Metals & Alloys--Mechanical Properties
ANODIZATION
DISLOCATIONS
DUCTILITY
FILMS
FLOW STRESS
LOW TEMPERATURE
MONOCRYSTALS
N50230* --Metals
Ceramics
& Other Materials--Metals & Alloys--Properties
Structure & Phase Studies
STRAIN HARDENING