New Strain Gauge Series For Compression Tests On Polymer Matrix Composite Materials

Unique Configuration Enables Standard Compression Tests on Composite Materials

Micro-Measurements®, a Vishay Precision Group, Inc. (VPG) brand, today announced the release of three CEA-Series strain gauges designed to perform standard compression tests on polymer matrix composite materials.

The new sensor patterns feature a unique configuration that is ideal for any strain measurement requiring close proximity to one-sided features, such as weld joints, structural discontinuities, or stress risers like holes and cracks.

“Structural designers have told us that finding the compression strength of composite materials is necessary and is the subject of ASTM Standard Test Method D6641,” said Bob Watson, director of engineering, Micro-Measurements®.

“The loading device recommended for use in this standard provides a 12.7 mm (0.5 in.) test section length and a test section width range of 12.7 to 30 mm (0.5 to 1.2 in.), making our new UB pattern geometry ideal for this testing.”

The 062UB, 125UB, and 250UB patterns are designed with both solder tabs placed on one side of the linear sensing grid, which allows these foil strain sensors to be properly oriented on the composite specimen, keeping the sensing grid centred in the test zone.

Available in 350 ohm to minimise self-heating, the UB patterns are made in the popular CEA-Series construction, which features a thin, flexible, cast polyimide carrier backing and encapsulation, and rugged copper-coated solder tabs that enable quick and simple soldering.

The UB patterns are also available with optional pre-attached lead wires, eliminating the chance of heat damage to the test specimen during soldering.