If the file is corrupt, it's gone. You can try third-party recovery software (google it) but chances are usually slim.
File corruption is always caused by failing hardware! You need to find and replace the failing component ASAP, before it spreads. It can be a drive about to fail, but it can also be something as simple as a bad cable or connector. The latter is a very real possibility if you use external drives.
A power cut during save can also corrupt files, but in that case it's a one-off incident.