S. Pathak, S. Supakul
Iowa State University,
United States
Keywords: Micro-Mechanical testing, extreme conditions, strain rate, temperature, DURIP
Summary:
We showcase the capabilities of the Alemnis in-situ micro-mechanical system for testing under extreme conditions of temperature (-150-to-1000C), a wide range of applied strain-rates (10-4 to 104/s) and high applied stresses. Traditional nano-to-microscale testing is typically conducted at quasistatic rates (i.e. strain rates of 10-5 to 10-2/s) and under ambient conditions (room temperature). However, the dynamic properties of the local regions of interest remain unexplored, especially at low/elevated temperatures. This 2021 ARO-DURIP funded instrument offers an exciting transformative solution, in which we are able to evaluate local material response over wide extremes of temperature, strain rates and loading conditions. This presentation describes the ability of the Alemnis indenter system to perform (1) high-throughput nanoindentation (Fig.1, see attached PDF), as well as other loading geometries such as (2) micropillar compression, (3) micro-tensile, and (4) micro 3-point bend testing over a wide range of (5) strain rates (10-3 to 103/s) (Fig.2-4) and (6) cryo and elevated temperature conditions (Fig. 4-5). We describe measured material properties (e.g. modulus, hardness, yield strength, fracture toughness, strain rate sensitivity, activation volume, and activation energy) on a wide range of material systems, including hierarchical multilayered nanocomposites, traditionally and additively manufactured metallic alloys, and biological materials.