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redicting how materials behave under stress is difficult, especially when only a small specimen or thin film is available for testing. One technique involves using an “indentor” to poke a probe into the material while accurately measuring the penetration depth and the force exerted. But analytical methods for inferring mechanical properties from such measurements are generally not reliable; and they cannot handle “graded” materials in which the composition varies with depth to provide variations of properties such as stiffness and resistance to excessive deformation. Now researchers affiliated with the Energy Laboratory have developed methods that perform such analyses in conjunction with a new generation of microindentors and nanoindentors. The indentor takes clear, continuous measurements of how penetration depth relates to applied force; and the analytical method translates those measurements into an unambiguous set of properties describing the specimen being tested. Based on this research, Instron Corporation is developing an instrument for analyzing homogeneous materials and is also incorporating the P