|About this Abstract
||MS&T22: Materials Science & Technology
||50 Years of Characterizing Structural Ceramics and Glasses: Recognizing the Contributions of George Quinn
||Failure Analysis of a Large SiC Component
||Kristin Breder, Eric Buchovecky, Ryan Koseski
|On-Site Speaker (Planned)
A large silicon carbide part was being inserted into a specific application assembly at a customer using heat shrinking. Sounds consistent with fracture were reported by the installing engineers within 20-30 seconds of inserting the part into a heated metal sleeve.
Based on fractographic analysis and finite element modeling, it is clear that the component failed due to the thermal gradient induced across the component in the process. The fracture origin was likely a grinding flaw, but surface features near the fracture origin were inside the specified tolerances. There did not appear to be any physical feature (e.g. inclusion, pore, micro-crack) or chemical inconsistency near the origin. Measurement of the mirror constant indicated a failure stress consistent with the stress level seen in the model. The customer was recommended to change the process conditions to account for the larger part to significantly reduce the thermal stresses during the process.