Deformations in a burning specimen and their effect on the heat transfer through a bulkhead

It is shown that a weak unloading wave propagates ahead of the combustion front in a 3Zr + 2WO$_3$ specimen pressed into a rigid nondestructable semiclosed shell. For a sufficiently high specimen ($\gtrsim$ 9 mm), this wave causes noticeable distortion near the end face before the combustion wave arrives there.