Measurement of stacking fault energy from dislocation interactions

摘要: The theories and methods applied to the determination of stacking fault energy (γ) using techniques direct observation dislocation configurations are reviewed. four principal methods, utilizing nodes, multiple ribbons, tetrahedra, faulted dipoles, discussed in detail. Different theoretical treatments compared wherever possible. Experimental procedures quantitative measurement reviewed, concentrating on transmission electron microscopy techniques. Detailed examples application each method given. For γ/μb range 2×10−4 5×10−3 (μ shear modulus,b Burgers vector), measurements nodes or ribbons favorable cases should permit determinations a precision 5 pct. larger values (up 12×10−3) can be made tetrahedra dipoles with less precision. Larger require high resolution studies dislocations; these not yet well established. Possible sources systematic bias discussed. Two significant problems remain concerning treatment core use anisotropic elasticity. It is prime importance characterize as carefully possible materials studied if accurate results desired.