Strength and Fracture Mechanisms of Nanostructured Metallic Materials Under Single Kinds of Loading

Resumo

The effect of nanostructuring on the strength and fracture mechanism of materials possessing different crystal lattices is analyzed on the basis of available reports and experimental data of the authors. The structure, the hardness, the crack resistance, and the strength and ductility characteristics of steel 10 (bcc lattice), aluminum alloy AK4-1 (fcc lattice), austenitic steel AISI 321 (fcc lattice) are studied after equal channel angular pressing (ECAP) and those of Grade 4 titanium (hcp lattice) are studied after a ECAP-conform process (ECAP-C). It is shown that the ultrafine-grained (UFG) structure produced by the ECAP affects ambiguously the static crack resistance of the materials studied. The type of the crystal lattice influences substantially the temperature behavior of the impact toughness of the studied materials with UFG structure.