Radiation phase states structural analysis

The thermophysical state of a material may be defined as the end result of prior thermal treatment and its interaction with mechanical deformation introduced in the final fabrication process. All of these conditions can have an effect on corrosion emd must be characterized for definitive analysis. Surface condition of a specimen may also have an important influence on corrosion rate. The thermophysical condition of a material under test may be affected by the exposure environment. For example, if the intended application for a given metal or alloy is as a component in a nuclear reactor, then care should be exercised to ensure that high neutron fluxes do not significantly alter predicted corrosion behavior. Radiation can enhance nucleation reactions, and this may result in precipitation at lower than normal temperatures, or precipitation of normally unstable phases. In addition, radiation can dramatically affect the defect structure of a material and, therefore, significantly... 

The analysis of the diffraction data showed that the irradiated crystals consist of a solid solution of the monomer and its polymer. After 40 Mrad of radiation, the crystals polymerize to about 70%, the resulting polytriacetylene crystal structure is shown in Scheme 5.8. Further irradiation and polymerization brings about a sudden phase change in the crystals to an amorphous "glassy state that no longer gives useful diffraction data. 

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