Laser interferometric dilatometer for low-expansion materials

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:7185845

Drotning, W D

The development of a high-precision dilatometer based on interferometry presents a number of challenges. This paper describes a laser interferometric dilatometer developed for high-precision thermal expansion measurements in the materials laboratory. The Sandia dilatometer uses dual-beam laser interferometry with a computer-controlled optical alignment feature to achieve high-precision length change measurements. This device has been modified to expand its measurement capabilities in a number of areas. A new thermal chamber has been incorporated which provides a range of measurement from 90 to 500 K while minimizing thermal effects on the optical portion of the instrument. A new specimen holder has been developed to cover this temperature range while accommodating a wider variety of specimen types. In particular, thin (1 mm) composites may be employed in the holder, which uses a single specimen, with only modest shape and preparation requirements, to provide absolute length change measurements. Tilt errors limit the overall performance of dilatometers based on dual-beam interferometry. Significant improvements in precision were demonstrated by incorporating a unique optical system which independently measures specimen holder tilt; tilt errors were corrected and a length change resolution near 0.4 microstrain was achieved. Expansion coefficient data obtained with the device agreed with established results on fused silica, platinum, and stainless steel. New expansion data were obtained from 90 to 293 K on stainless steel, NBS Standard Reference Material 738.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 7185845
• Report Number(s): SAND-87-2806C; CONF-880606-4; ON: DE88012329
• Country of Publication: United States
• Language: English

Related Subjects

656002* -- Condensed Matter Physics-- General Techniques in Condensed Matter-- (1987-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
CHALCOGENIDES
CHROMIUM ALLOYS
COMPOSITE MATERIALS
CORROSION RESISTANT ALLOYS
DATA
DILATOMETRY
ELEMENTS
EXPANSION
EXPERIMENTAL DATA
INFORMATION
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS
METALS
MINERALS
NUMERICAL DATA
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PERFORMANCE
PLATINUM
PLATINUM METALS
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SPECIFICATIONS
STAINLESS STEELS
STEELS
THERMAL ANALYSIS
THERMAL EXPANSION
TRANSITION ELEMENTS