Mechanisms of intergranular cavity nucleation and growth during creep

Journal Article · Sat Jan 01 04:00:00 EST 1983 · Scr. Metall.; (United States)

DOI:https://doi.org/10.1016/0036-9748(83)90064-9· OSTI ID:5581640

Goods, S H; Nieh, T G

It is generally recognized that creep-rupture of metals and alloys is caused by the formation, growth and coalescence of grain boundary cavities. A large body of literature suggests that the nucleation of cavities rather than their growth controls the fracture of materials over a wide range of temperatures, especially at temperatures associated with creep deformation. Thus when cavities such as voids or gas bubbles exist in materials prior to the beginning of deformation a severe loss in creep ductility often results. Because cavities are such a potent source of embrittlement, a great many studies have attempted to illustrate both experimentally and theoretically the role of cavity growth in the creep fracture process. However, understanding the effect of grain boundary cavities on creep fracture is complicated by the inability to accurately characterize the cavity structure prior to the onset and during creep deformation. For materials in which cavitation, the simultaneous nucleation and growth of cavities, occurs continously during creep, the kinetics of cavity growth are often obscured by the kinetics of cavity nucleation. In order to understand the importance of either cavity nucleation or growth in creep fracture, the nucleation event must be clearly and unambiguously separated from cavity growth processes. In this article the critical factors which must be considered in the study of creep cavitation are discussed. The authors first examine a number of key observations regarding the processes responsible for cavity nucleation, then discuss the importance of nucleation in creep fracture and conclude with an analysis of important theoretical and experimental results found in the recent literature which illustrate the micromechanics of cavity growth.

• Research Organization: Sandia National Laboratories, Livermore, CA 94550
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5581640
• Journal Information: Scr. Metall.; (United States), Journal Name: Scr. Metall.; (United States) Vol. 17:1; ISSN SCRMB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOYS
CAVITIES
CREEP
CRYSTAL STRUCTURE
DATA ANALYSIS
DEFORMATION
DUCTILITY
ELEMENTS
EMBRITTLEMENT
FAILURES
FRACTURE MECHANICS
GRAIN BOUNDARIES
GRAIN GROWTH
MECHANICAL PROPERTIES
MECHANICS
METALS
MICROSTRUCTURE
NUCLEATION
RUPTURES
TEMPERATURE DEPENDENCE
TENSILE PROPERTIES