Session: 02-01 Mechanical Behavior of Ceramics & Composites

Paper Number: 83010

83010 - Advancement of Electrical Resistance Towards Monitoring Crack Growth in SiC Based Composites at Elevated Temperatures 

Electrical resistance is a health monitoring technique that can be used to detect in situ changes to SiC based material as damage occurs. Any damage to the composite will increase the resistance in the path of the constant following current and will be captured using a four-probe method. To enhance sensitivity to damage detection, high conductive carbon monofilaments were incorporated into a laminate pre-preg melt infiltrated (MI) composites while manufacturing. The carbon rods were inserted in the form of SCS-ultra fibers which consist of 33 µm carbon core. Some material variations had the carbon extending through the length of the composite (continuous) and in other cases they were discontinuous. Tension-tension fatigue test was conducted at 815 °C in a static furnace. Electrical resistance and acoustic emission were used as health techniques and monitored during the test. It was apparent that the carbon did not play a major role in enhancing the sensitivity to damage in the MI system due the presence of high conductive Si phase. Microscopy was conducted to better understand the crack morphology. A ply level electric circuit was constructed based on ply resistivities at temperature to corelate the resistance change in the MI material with crack growth.

Presenting Author: Joseph El Rassi The University of Akron

Presenting Author Biography: Joseph El Rassi is a PhD student at the University of Akron, Akron Ohio. His research focus is understanding crack morphology and damage progression in SiC-based composite systems at room temperature as well as elevated temperatures.

Authors:

Joseph El Rassi The University of Akron
Gregory N. Morscher The University of Akron