Axial Yield Strengths and Two Successive Phase Transition Stresses for Crystalline Silicon

Shock wave experiments with inclined prisms have been used to determine the compression for shocks propagated along three axes of single-crystal Si. At stresses less than about 200 kbar, the shocks along the 〈110〉 and 〈1111〉 axes exhibited four wave structures. The first three waves were taken to be related to the Hugoniot Elastic Limit and to two succeeding polymorphic phase transitions. Scatter in the magnitude of the HEL along the 〈100〉 axis may indicate mixing between the elastic wave and the first phase transition wave.