History
The Hopkinson Pressure Bar was first suggested by Bertram Hopkinson in 1914 as a way to measure stress pulse propagation in a metal bar. Later, in 1949 H. Kolsky refined Hopkinson's technique by using two Hopkinson bars in series, now known as the split-Hopkinson bar, to measure stress and strain, incorporating advancements in the cathode ray oscilloscopes in conjunction with electrical condenser units to record the pressure wave propagation in the pressure bars as pioneered by RM Davies a year earlier in 1948.
Later modifications have allowed for tensile, compression, and torsion testing.
Read more about this topic: Split-Hopkinson Pressure Bar
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