کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1582755 | 1514872 | 2008 | 7 صفحه PDF | دانلود رایگان |
The author proposes the critical events controlling cleavage at various temperatures: at a very low temperature (−196 °C), critical event is the nucleation of a crack in ferrite at the precrack tip. At a moderate low temperature (around −100 °C), the critical event is the propagation of a carbide crack into the ferrite grain. With increasing temperature (around DBTT ∼−80 °C), the carbide crack eligible to propagate into the ferrite grain should be the one initiated by a critical strain higher than that to initiate a carbide crack at low temperatures. The higher critical strain increases the flow stress by work hardening for making up the effect of lowering yield stress. At a higher temperature (−30 °C) after the crack tip is blunted to more than 60 μm and a fibrous crack extends, the critical event for cleavage fracture is the propagation of a grain-sized crack.
Journal: Materials Science and Engineering: A - Volume 486, Issues 1–2, 15 July 2008, Pages 369–375