Hi Becky, no it isn't, however Altertx does two things to help ensure you don't lose your work.
Firstly it autosaves, by default I believe every 10 minutes, but you can set this value to be more/less often if you go to options - edit user settings. Autosaves files can be found quite easily in a folder but the path alludes me off the top of my head and I'm mobile at the moment!
Secondly it creates a .bak file every time you got save. A .bak file is stores in the same location as the workflow and is a copy of the version at the point of the previous save. You can convert a .bak file to an Altertx workflow file by changing the extension to .yxmd