Outlining Foil Strain Gauges: Technology and Types Outlining Foil Strain Gauges: Technology and Types | HBM

Outlining Foil Strain Gauges

A foil strain gauge is a sensor for measuring relative changes in the length of a material (strain) due to applied forces. This deformation is registered as compression or tension and is greatly influenced by the elastic properties of the tested material. Positive strain refers to instances where mechanical components have elongated while negative strain describes materials that are compressed.

The Measuring Principles of Foil Strain Gauges

Foil strain gauges are used to determine the value and direction of strain. This is achieved by a measuring grid that is usually installed on a material surface to acquire applied strain as a factor of changes in electrical resistance against the foil strain gauge’s nominal resistance and its sensitivity factor. It registers compression as a decrease in electrical resistance and elongation as an increase.

To calculate material stresses (Experimental stress analysis) the strain values are coupled with a material’s physical properties such as its Young’s modulus (Hooke’s law).

Alternate applications for strain gauges are transducers such as load cells, force-, torque- and pressure transducers.

There are thousands of distinct foil strain gauges available from HBM including linear, rosette, torsion/shear, full bridge, and chain formats.

  • Linear strain gauges are preferable for measuring strain across a single plane of direction
  • Rosette foil strain gauges feature dual measuring grids to offset strain measurements at a 90° angle to measure biaxial stress
  • Torsion/shear strain gauges feature uniquely arranged measuring grids for determining the shear stress of torsion bars
  • Double linear foil strain gauges feature parallel measuring grids for acquiring perpendicular stress in bending beams
  • Full bridge strain gauges feature 4 integrated measuring grids for robust strain measurements of shear stresses in tension and compression bars
  • Chain foil strain gauges are equipped with a number of smaller measuring grids to acquire shear force gradients across the measuring bridge 

Foil Strain Gauges from HBM

HBM is an expert in the manufacture and supply of leading measurement instrumentation for a broad range of applications. Our foil strain gauges are routinely used for Experimental Stress Analysis, durability testing, and transducer manufacturing, providing unrivalled accuracy in the field of strain analysis.

If you would like any more information about our measurement components for stress analysis, please do not hesitate to contact us.