Understanding Phase Transformations from Microstructure Evolution

by Dr Andreas Leineweber (Institute of Materials Science)

Thursday 28 Sept 2017, 13:45 → 15:00 Europe/Zurich

112/R-028 (CERN)

In the course of materials processing new phases are generated via processes which are called phase transformations in physical metallurgy/materials or simply chemical reactions in chemistry. Thereby, the atomic structure is rearranged in a more or less cooperative manner, frequently involving diffusive mass transport to locally adapt composition. The result of such processes are characteristic microstructures. These microstructures can contain important information to understand the course and mechanism of the phase transformations, which have preceded.

In my talk examples, present of phase transformation studies in metallic systems are presented. The necessity is stressed of thorough characterisation of the microstructures using complementary analysis techniques like X-ray diffraction as well as optical, scanning electron and transmission electron microscopy. Pitfalls are highlighted, which turn up in case of uncritical belief in incomplete literature data concerning phase equilibria or crystal structure.