The Blue Badge is recognised across Europe, it allows you to make use of the same parking concessions that the country you are in allows its own citizens with disability. Parking concessions for holders of a disabled parking card do vary from country to country so it's important to know where, when and for how long you can park in each country.
This leaflet by the AA contains a translation for each country, which can be printed out and displayed with your badge. This explains to police and parking attendants in their own language that as a foreign visitor you are entitled to the same parking concessions as disabled residents, and that your parking is legal.
You can find out more about using your disabled badge in Europe in this useful guide.