Rough Surface (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption The roughness of the alumina/PMMA hybrid ceramic controls the strength of the interfaces, which is critical in determining the material's overall toughness as it affects the sliding process in the polymeric "mortar" layers. Credit Robert Ritchie, Berkeley Lab Usage Restrictions None 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.