| About this Abstract |
| Meeting |
Materials Science & Technology 2011
|
| Symposium
|
Fatigue and Microstructure: A Symposium on Recent Advances
|
| Presentation Title |
On Microstructure and Crack Path Mechanisms in High Temperature Materials |
| Author(s) |
Hamouda Ghonem |
| On-Site Speaker (Planned) |
Hamouda Ghonem |
| Abstract Scope |
A focus is made on the concept that the fracture mechanisms in high temperature alloys are governed by the slip process in the crack tip region. This concept is applied to Widmanstatten and fully lamellar titanium alloys as well as nickel-based superalloys in order to explain the different fracture modes observed under effects of the loading frequency and temperature. In the Widmanstatten microstructure, it is proposed that interactions of slip bands with both the colony boundary and the grain boundary result in transcolony and intergranular fracture, respectively. In fully lamellar microstructure, the predominant transgranular fracture occurring along heavily shear slip bands is categorized in terms of the angle between the corresponding crack path and the lamella long axis direction within a single colony. In nickel based superalloys, the intergranualr cracking mechanism is correlated with the grain boundary sliding which is experimentally measured and numerically correlated with the slip band spacing. |
| Proceedings Inclusion? |
Definite: A CD-only volume |