EVALUATION OF NEW TECHNIQUE TO ESTIMATE YIELD STRESS IN BRITTLE MATERIALS VIA SPHERICAL INDENTATION TESTING
Conference Paper
Overview
Identity
Additional Document Info
View All
Overview
abstract
2019 The American Ceramic Society. Instrumented indentation testing provides the means to measure many mechanical properties and characteristics of materials. One such mechanical property that can be ascertained from indentation testing is a material's yield stress, the stress corresponding to the onset of permanent deformation. In britde materials such as ceramics and glasses, traditional testing methods fall short of precisely establishing the yield stress. A new technique to estimate the yield stress is under development and described here. It utilizes the sensing and interpreting of the initiation of a residual surface impression through the change of the instantaneous contact-stiffness3/load (S3/P) as measured by load and depth-sensing indentation with spherical indenters. Several brittle materials (borosilicate, soda-lime silicate, and bulk metallic glass) are evaluated, and the test method and manner of interpreting the yield-like response through S3/P are described.
