摘要：

Rapidly quenched REP powders produced by melt atomization (spraying) are obviously characterized by the same effect of the quenching rate on structural features as in conventional solid-state quenching. However, the critical cooling rate determined from the TTT diagram for the phase transformation of the melt during atomization-crystallization is much higher than its value for the TTT diagram for conventional solid-state quenching. Important features of rapidly quenched powders, high dispersity of dendritic structures and formation of micro- and nanograin structures, determine the features of carbide and boride precipitation. Direct nuclear methods of activation autoradiography on carbon, track autoradiography on boron, metallography, SEM, EDX, etc., are used in the study. The structure features, including carbon and boron distribution, carbide and boride precipitation, the lattice parameter of an austenite solid solution for rapidly quenched REP powders, PM HIP compacts, and products such as nuclear fuel cladding tubes made of austenitic stainless steels and their counterparts produced by traditional technology, are revealed and analyzed taking into account the role of carbon and behaviour, precipitation of carbide and boride, and the influence of non-equilibrium states of the studied austenitic steels.

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