Ultra-High Accuracy Thermal Expansion Measurement

Southern Research Institute has developed a unique facility for measuring thermal expansion with ultra-high accuracy from 300 K down to below 15 K. Using interferometers and a proprietary optical flagging system, CTE accuracy of better than 20 parts-per-billion is standard. For materials that do not tend to bend or flex, CTE accuracy of better than 5 parts-per-billion is possible (based on 8" sample with 20 K delta T). Sample sizes can range from 1 cm to 1 meter in length with cross-sections up to 20 cm in diameter.

• Test coupons (1 to 8 inches long)
• Tubes and Struts (up to 1 meter)
• Honeycomb Core Material
• Low-CTE Composite Samples (various configurations)
• Low-CTE Glass Samples (mirror segments and machined specimens)

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Absolute Accuracy

• Expansion data generated on NIST Cu SRM 736
• NIST traceable silicon diode temperature sensors
• No reference standards or back-out factors
• Cosine error minimized
• Abbé error largely self-canceling
• Optics thermal drift self-canceling
• Large, continuous data density

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Precision to PPB

• Quantification of composite CTE
• Multiple thermal cycles
• Acceptance and Performance Testing

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Cryogenic Capability

• Temperatures below 15K
• Same accuracy and precision as room temperature data
• Data collected on cool-down and warm-up

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Ultrasonic Spectroscopy
Structure Distortion Measurement
Instrumentation and Software Support
Cryogenic Testing

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