There's no provision to expel a member state, but TEU Post seven provides for the suspension of certain rights. Released in the Treaty of Amsterdam, Report 7 outlines that if a member persistently breaches the EU's founding concepts (liberty, democracy, human legal rights and so forth, outlined in TEU Write-up https://stephenb826xfn9.bloggazza.com/28927493/login-member4d-fundamentals-explained