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Measurement of Compressive Stress-Strain Response at Small-Strains
Published on: December 5, 2025
Capacitance-torsion balance for measuring small stresses and strains
1Department of Metallurgical Engineering, Ohio State University, Columbus, Ohio 43210Varian Associates, 611 Hansen Way, Palo Alto, California 94303Department of Metallurgical Engineering, Ohio State University, Columbus, Ohio 43210.
The Review of Scientific Instruments
|June 1, 1978
Summary
A new, affordable capacitance-torsion balance measures small forces and displacements continuously. This versatile instrument functions as a dilatometer or microbalance, offering adjustable ranges and consistent sensitivity for remote sample analysis.
Area of Science:
- Physics
- Materials Science
- Instrumentation
Background:
- Accurate measurement of small forces and displacements is crucial in various scientific fields.
- Existing instruments may be expensive, complex, or lack simultaneous measurement capabilities.
Purpose of the Study:
- To develop a versatile and inexpensive capacitance-torsion balance.
- To enable simultaneous and continuous measurement of small forces and displacements.
- To explore its utility as a dilatometer and microbalance.
Main Methods:
- Development of a novel capacitance-torsion balance apparatus.
- Utilizing capacitance changes to detect force and displacement.
- Adjusting the geometrical configuration to set independent load and displacement ranges.
Main Results:
- The instrument successfully measures small forces and displacements simultaneously and continuously.
- Achieved an output voltage change of 1 V for a 3 g load change and 5x10(-5) m displacement.
- Demonstrated independent adjustability of load and displacement ranges.
- Sensitivity remained constant irrespective of the chosen range.
Conclusions:
- The developed capacitance-torsion balance is a versatile, inexpensive tool for precise measurements.
- Its adaptability makes it suitable for applications requiring dilatometry or microbalance functionality.
- The instrument offers a valuable solution for remote sample analysis requiring simultaneous force and displacement detection.
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