The reaction zones of normal and overdriven detonation waves in a number of
solid HE were studied by recording the shock-wave luminosity in chloroform
placed at the end of a high-explosive (HE) charge. The data obtained have
led to some conclusions on the regularities of HE decomposition in a detona
tion wave. Thus, in a powerful solid HE, the heterogeneity of the charge pl
ays a decisive role in the formation of a chemical spike. In this case, the
time of reaction of heterogeneous HE correlates with the Jouguet pressure
rather than with the sensitivity of the HE. The experimental parameters of
the chemical spike are in good agreement with calculations on an extrapolat
ed shock adiabat of the HE. This, however, does not indicate that the fract
ion of the HE decomposed directly at the detonation front is small but only
shows that it depends smoothly on the front parameters. In overdriven deto
nation waves, an increase in the overcompression pressure is accompanied by
an increase in the fraction of the HE decomposed directly at the front, an
d with a relatively large increase in pressure, the chemical spike complete
ly disappears. In TATB and TATB-based HE, this occurs at a pressure of 40 G
Pa.