Precision interferometric dilatometer
Abstract
An improved double Michelson laser interferometric dilatometer with an inexpensive automatic signal processor is described. The unit is suitable for studying materials having near-zero coefficients of thermal expansion (CTE) ranging from 100 to 450 K. Delta L/L values to a resolution of less than 10 to the minus 7th power and instantaneous CTE values (to less than 10 to the minus 8th power per K) can be plotted in real time at regular intervals ( 30 s) to give time-related absolute expansion data of noncontacted samples of arbitrary shape or size.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- August 1985
- Bibcode:
- 1985STIN...8614574W
- Keywords:
-
- Dilatometry;
- Extensometers;
- Michelson Interferometers;
- Signal Processing;
- Thermal Expansion;
- Accuracy;
- Automatic Control;
- Coefficients;
- Distance Measuring Equipment;
- Errors;
- Glass;
- Helium-Neon Lasers;
- Interferometry;
- Laser Outputs;
- Liquid Nitrogen;
- Mirrors;
- Precision;
- Sampling;
- Thermal Stability;
- Vacuum Apparatus;
- Instrumentation and Photography