Irradiated steels structure and properties instability caused by latent energy

In this paper the latent energy Es linked with crystal structure defects has been used as one of parameters describing metallic materials stability to synergetic influence of the irradiation, the thermal and mechanical stress. On the basis of the first law of the thermodynamic the value Es was estimated from the experiments on sampled deformation in microcalorimeter with simultaneous estimation of the evolved heat (Q) and the work expended on the deformation (A), here Es=A-Q. The experimental data on the Es function revealing at plastic flow of austenitic steels for different temperature-rate ranges and the investigation of latent energy influence on deformation induced martensite γ→α' transformation in metastable materials are discussed. By mean of transmitted electron microscopy and calorimetry the dislocation structure evolution and associated with it progress of energy accumulation and dissipation during 12Cr18Ni10Ti steel samples tension were investigated. The regularities of accumulated energy changes as function of deformation level were determined. With the help of the developed numerical technique of heat dissipation curve real form recovery the values of A,Q and Es in the discrete flow conditions of steels irradiated by the high energy particles were determined. It was shown that with the increase of deformation level the ability increases to dissipate the supplying mechanical energy for nonirradiated as well as for irradiated materials. The irradiated by neutrons steel possesses the less ability to store the energy during tensile process than in nonirradiated state. The important latent energy role in the processes of the α'- martensite nucleation and development at the steel deformation was revealed. It was shown, that the α'-martensite formation occurred on the definite flow stage only after the critical for condition energy Es was stored