About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
|
Mechanical Behavior at the Nanoscale VII
|
Presentation Title |
What is the Maximum Constant Strain Rate Achievable by a Given Indentation System? |
Author(s) |
Warren Carl Oliver, Phani P. Sudharshan |
On-Site Speaker (Planned) |
Warren Carl Oliver |
Abstract Scope |
Constant strain rate (CSR) indentation test also known as constant Pdot / P test is one of the ideal ways to measure hardness as the deformation structure is believed to be retained during testing. A typical CSR indentation test with a Berkovich indenter involves exponential load-time history to achieve a constant ratio of Pdot / P. This presents a challenge from an instrumentation perspective as the loading rate increases with load and desired constant strain rate, thereby limiting the maximum achievable strain rate. In this work, we present a simple theoretical treatment to analytically determine the maximum achievable constant strain rate for a given instrument that depends on several factors including, actuator mass, stiffness, damping, load and displacement time constant, data acquisition rate, control loop rate etc., Guidelines for the choice of instrument dynamic and electronic parameters will be presented to expand the range of strain rate. |
Proceedings Inclusion? |
Planned: |
Keywords |
Characterization, Mechanical Properties, Other |