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Temperature-Induced Internal Stress Influence on Specimens in Indentation Tests
Shunbo Wang1, Xianke Li1, Hongwei Zhao1,2,3
1School of Mechanical and Aerospace Engineering, Jilin University, Changchun 130025, China.
Micromachines
|July 27, 2022
Summary
Finite element analysis (FEA) investigated temperature effects on indentation tests. Thermal expansion of the stage significantly impacts accuracy, especially at -196 °C, causing over 3% error in mechanical properties.
Area of Science:
- Materials Science
- Mechanical Engineering
- Computational Modeling
Background:
- Indentation testing is crucial for determining material mechanical properties.
- Temperature variations can introduce significant errors in indentation test results.
- Existing models often neglect the thermal expansion of testing apparatus.
Purpose of the Study:
- To investigate factors influencing internal stress during indentation tests.
- To understand and quantify test errors caused by temperature environments.
- To explore the impact of thermal expansion of the fixed stage on specimens.
Main Methods:
- Utilized finite element analysis (FEA) modeling for simulations.
- Analyzed the influence of specimen parameters (thickness, width, elastic modulus).
- Evaluated external conditions including stage and glue properties.
Main Results:
- Identified thermal expansion of the fixed stage as a key error source.
- Quantified simultaneous errors exceeding 3% in hardness and elastic modulus at -196 °C.
- Addressed technical issues related to specimen and environmental parameters.
Conclusions:
- Determined preferred operational conditions for accurate indentation testing at various temperatures.
- Highlighted the importance of accounting for thermal expansion in low-temperature indentation.
- Provided guidance for experiments seeking precise mechanical parameter determination.
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