What version of AxCrypt is that?
In any case, that should not happen. While decrypting – the original encrypted file should be untouched. Then the output should be flushed to disk, and finally the decrypted file will be partially wiped and then deleted.
Since you mention a temp file, that indicates that you’re using version 1 of AxCrypt which is no longer supported since quite some time.
Can you give more details about the files, sizes, dates, and names (at least the extensions, you can replace ‘your filename’ with something else).
Unfortunately, if a PC crashes at just the wrong time after a lot of disk writing, there’s always a slight risk of something going permanently wrong. This happens in extreme cases with all software, especially when the system is optimized for speed (which user PC’s typically are with write caching enabled for example).