J. Phys. Colloques
Volume 46, Number C4, Avril 1985International Conference on the Structure and Properties of Internal Interfaces
|Page(s)||C4-555 - C4-566|
J. Phys. Colloques 46 (1985) C4-555-C4-566
STRUCTURAL EFFECTS ON GRAIN BOUNDARY SEGREGATION, HARDENING AND FRACTURET. Watanabe
Department of Materials Science, Faculty of Engineering, Tohoku University, Sendai 980, Japan
Recent experimental studies of structural effects on grain boundary segregation, hardening and fracture in metals and alloys are discussed. It has been found that grain boundary segregation, hardening and fracture are difficult to occur at low angle boundaries and coincidence boundaries which are both low energy grain boundaries. On the other hand, high angle general (so called "random") boundaries can be preferential sites for these boundary phenomena. In polycrystals, their fracture mode and fracture behaviour have been found to depend on the grain boundary character distribution in them. Intergranular fracture will occur typically in a polycrystal with a high frequency of random boundaries. The grain boundary character distributions in real polycrystalline materials produced by different fabrication processes are discussed. A new idea "Grain Boundary Design" for strong and ductile polycrystals which has been proposed recently is mentioned briefly.