Using An AC Field Strengthens Ceramics (IMAGE) North Carolina State University Caption By applying a 60 Hertz alternating current field, researchers were able to reduce the grain size of ceramics by 63 percent -- and eliminated porosity at 1,250 degrees Celsius, as opposed to the 1,500 degrees Celsius needed without the electric field. Credit Dr. Hans Conrad, North Carolina State University Usage Restrictions Photo credit must be given. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.