Display custom user profile field as name in articles
You can use the Realname module to override the display name with the values of one or more fields: 


  The RealName module allows the administrator to choose fields from the
  user profile that will be used to add a "real name" element (method)
  to a user object. Hook_user is used to automatically add this to any
  user object that is loaded. It will also optionally set all nodes and
  comments to show this name.