An experimental method to measure dynamic stress–strain relationship of materials at high strain rates

• Radial velocities of specimens in SHPB are captured by photonic Doppler velocimetry system.
• Dynamic stress–strain relationships are obtained by measuring radial velocities and end-surface stresses.
• The experimental is useful for measuring dynamic stress-strain relationships for large size specimens.

In this paper, an experimental method for measuring dynamic behavior of materials at high strain rates is developed. The strain and stress of a specimen are obtained using a high-precision photonic Doppler velocimetry system and a sensitive polyvinylidene fluoride thin-film sensor respectively. Based on the assumptions of one-dimensional stress state and negligible volume change at plastic deformation stage, the dynamic stress–strain relationship of materials can be determined. Using Al-2024T351 alloy and copper as model materials, the method demonstrates its effectiveness in measuring dynamic behavior of materials at high strain rates.