September 11, 2008: SRI International is using a new scanning electron microscope (SEM) to further develop fracture surface topography analysis (FRASTA) technology, enabling failure analysis down to nanometer scales. Application areas include fracture mechanics, micro-electromechanical systems (MEMS), coatings, ceramics, and biology.
Elionix Inc., a Japanese SEM manufacturer, is providing the 3D microscope to SRI in exchange for technical feedback on how to further utilize the equipment.
“This research partnership between SRI International and Elionix will lead to improved techniques for the research and failure analysis communities,” said Osamu Karatsu, executive director of SRI Japan. “The equipment will help us advance SRI’s FRASTA technology, and Elionix will obtain new ideas on how to improve and extend the capabilities of its scanning electron microscope.”
FRASTA analyzes the topographies of conjugate fracture surfaces, allowing a failure event to be replayed in microscopic detail. Current efforts aim to generate the microfracture evolution data necessary for computational models that predict aircraft component lifetimes. SRI researchers and engineers will also use this SEM for problem solving in many other areas of materials science, microelectronics, and biology.
A ceramic surface seen using Elionix’ e-RAM 8900FE 3D electron roughness analyzing microscope.
“A conventional SEM produces high-resolution images with deep depth-of-focus, but does not quantify surface topography,” noted SRI’s Takao Kobayashi. “Until now, FRASTA was limited to resolutions obtainable with optical microscopes, about 1000×. Elionix’s SEM can characterize topography at any magnification from 10× to 300,000×, providing quantitative 3D topographic maps and contrast images of complex, rough surfaces, as well as surfaces with delicate, ultra-fine features.”
The high-resolution capability is necessary for a current SRI research project that addresses an important safety issue with a hydrogen economy — how high-pressure hydrogen gas interacts with and embrittles the microstructures of steels used in pressure vessels and pipelines.
SRI’s FRASTA technology has been licensed to NASA in the US and to three Japanese companies including Mitsubishi Heavy Industries, Osaka Gas Company, and Chubu Electric Power Co.