GJB 8375-2015 in English

Technical background of the standard

This standard was developed by the China Academy of Engineering Physics in collaboration with Northwestern Polytechnical University and other institutions to meet the performance evaluation needs of metal materials in military equipment under high strain rate load environments such as explosion impact and projectile penetration. Compared with static tests, dynamic torsion tests can more truly reflect the shear resistance of materials in actual combat environments.

Analysis of core test equipment

Comparison of key technical indicators

Specimen preparation specifications

The standard clearly requires the use of thin-walled tubular specimens, and its key technical parameters include:

1. Wall thickness/inner diameter ≤0.2
2. Recommended connection method: Adhesive connection
3. Each group of valid specimens must be ≥ 5 pieces
4. Thickness measurement accuracy must reach 0.005mm

Key formulas for data processing

Core calculation based on one-dimensional stress wave theory:

 Shear stressτ(t) = (JbRs/JsRb)Gb[εI(t)+εR(t)-εT(t)] Strain rateγ̇(t) = (2RbCb/Rsl)[εT(t)+εR(t)-εI(t)] 

Implementation suggestions

1. Waveguide rod calibration: Regularly test the shear modulus G_b and wave velocity C<sub>b of the TC4 titanium alloy rod.
2. Signal processing: Use symmetrical arrangement of double strain gauges to eliminate bending wave interference
3. Quality control: The sample must be strictly cured for more than 24 hours after bonding</sub>