Evolution of Dislocation Structure in a Ni3Al Single Crystal Under the Conditions of High-Temperature Superplasticity

摘要

The evolution of defective structure in a single crystal of a Ni3Al-base intermetallic with iron and chromium additives under the conditions of superplasticity (delta = 140%) is studied by transmission electron microscopy. The tensile deformation is performed a 1150A degrees C. Planar flaws and recrystallized grains are detected in the fractured zone of the metal. The mechanisms of high-temperature superplasticity of alloys based on Ni3Al intermetallic are discussed.