|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Fracture: 65 Years after the Weibull Distribution and the Williams Singularity
||Fracture Toughness of Silicon by Variable Temperature Micropillar Splitting
||Carmen Lauener, Ming Chen, Jeff Wheeler
|On-Site Speaker (Planned)
Classically, silicon is known as a brittle material, whose sharp brittle-ductile transition (BDT) occurs within 1-2°C at a temperature between 500 and 800°C depending on the microstructure, strain rate, and crystal orientation. A recent study using the notched single cantilever beam geometry revealed a gradual increase in toughness, KC, with temperature, rather than a sharp BDT. Furthermore, the crack morphologies were observed to vary significantly, particularly between 300-400°C. To investigate this phenomenon in greater detail, the pillar splitting geometry was employed in combination with lithographically produced silicon pillars. A transition in toughness was observed to begin between 150 and 175°C with the values rising to ~1.7 MPa√m at 275°C before the pillars ceased to split. In addition, experimental issues such as pillar manufacturing methods and the effect of inaccurate indenter positioning were investigated at ambient temperatures.
||Planned: Supplemental Proceedings volume