Premartensitic microstructures as seen in the high-resolution electron microscope: A study of a Ni-Al alloy (open access)

Premartensitic microstructures as seen in the high-resolution electron microscope: A study of a Ni-Al alloy

The present study indicates that the B2 ..beta..-phase in quenched Ni/sub 62.5/Al/sub 37.5/ is distorted by displacement waves involving a planar shufflin of atoms resembling the final 7R martensite structure and with wavelenghts of the order of 1.3 nm. The appearance of a <110><110> type modulation with the indicated periodicity corresponds well with recent inelastic neutron scattering results which reveal nonlinear behavior in the TA<110> phonon dispersion curve around the same wavelengths indicating a partial lattice softening for such waves. In bulk material all six equivalent wave-vectors are equally present. These distortional modulations are configured in some form of three-dimensional assembly. Following the interpretation given above, it can be concluded that a one-dimensional domain structure along one of six <110> directions may exist. However, the beating of six displacement waves with apparently uncorrelated phase and wavelengths rules out the existence of a ''conventional'' three-dimensional domain structure. For this reason it is uncertain whether much more information can be gained from such image simulations. There are now numerous indications that the underlying structure to the tweed contrast in this alloy is a precursor effect of the martensitic transformation. However, a detailed description of the effective correlation between the distorted parent phase …
Date: February 12, 1988
Creator: Schryvers, D.; Tanner, L. & Van Tendeloo, G.
Object Type: Article
System: The UNT Digital Library
Texas Register, Volume 13, Number 12, Pages 749-816, February 12, 1988 (open access)

Texas Register, Volume 13, Number 12, Pages 749-816, February 12, 1988

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: February 12, 1988
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Mini-ß Insertion For The RHIC Lattice (open access)

Mini-ß Insertion For The RHIC Lattice

None
Date: February 12, 1988
Creator: Y., Lee S.
Object Type: Report
System: The UNT Digital Library
Acquired Immune Deficiency Syndrome and Military Manpower Policy (open access)

Acquired Immune Deficiency Syndrome and Military Manpower Policy

This issue brief will discuss issues dealing with military manpower policy and the AIDS virus, including the level of the AIDS infection or HIV infection rates in the military; efforts to control the spread of AIDS to and among military personnel; and AIDS in the context of military personnel stationed overseas.
Date: February 12, 1988
Creator: Burrelli, David F.
Object Type: Report
System: The UNT Digital Library