Mechanical testing of solid materials at the micro-scale

Abstract

Successful design and fabrication of structures and systems at the micro-scale requires a sound theoretical understanding and reliable experimental data on the mechanical behavior of materials at that scale. Generation of experimental data requires accurate, robust, reliable, versatile and yet simple micro-scale mechanical testing devices. This thesis describes the design, development and applications of materials testing technologies at the micro-scale. Using the rectilinear travel characteristics of compound flexures, two novel testing machines have been designed and built to conduct tension, bending and indentation tests in the force regime of 10 pN - 35 N and displacement regime of 20 nm - 6 mm. These machines have been used in measuring the mechanical properties of free-standing gold thin films, rolled metallic foils, elastomeric fibers and other materials. Numerical simulations of the mechanical behavior of gold thin films and rolled copper foils have been conducted and compared with experimental results. Microstructural investigations into deformation mechanisms of the free-standing gold thin films have also been conducted.