LOW-POWER PULSING OF STRAIN GAGES ON PLASTIC MATERIALS

Technical Report · Tue Sep 25 04:00:00 EDT 1962

OSTI ID:4752484

Makerov, C E

An experimental study was made to obtain accurate strains from strain gages on plastic materials. By using short-duration, high-voltage pulses (25 and 50 mu sec at 55 volts) at low repetitive rates (2 cps), the power input into the strain gage was kept low (below 2 1/2 milliwatts), thereby minimizing the local temperature rise ( DELTA T = 1 deg F) and minimizing the loss in the material's modulus ( DELTA E = -800 psi/ deg F). It was determined also that sensitivity of strain gages increases linearly to 61 mu v/ mu epsilon with 55-volt pulses, which is a five- to tenfold increase over the d-c type of strain-gage instrumentation. A full range of tensile-tocompressive strains ( plus or minus 1000 mu in./in.) was induced in a plastic beam in a constant-moment fixture, and comparisons were made between d-c and pulsed type of data acquisition. From these parameters, a ten-channel unit is now being designed for stress analysis tests, both static and dynamic. (auth)

• Research Organization: California. Univ., Livermore. Lawrence Radiation Lab.
• DOE Contract Number: W-7405-ENG-48
• NSA Number: NSA-16-033157
• OSTI ID: 4752484
• Report Number(s): UCRL-7071
• Country of Publication: United States
• Language: English

Related Subjects

CURRENTS
ELECTRIC POTENTIAL
ELECTRONIC EQUIPMENT
ENGINEERING AND EQUIPMENT
FREQUENCY
GAGES
LOSSES
MEASURED VALUES
POLYMERS
POWER
PULSES
SENSITIVITY
STRESSES
TEMPERATURE
TENSILE PROPERTIES