Can the spell focus items for the Artificer Enhanced Arcane Focus be expanded to tools or even hammer weapons? I would love to put this on a light hammer or warhammer for my artificer focus.

RAW, it needs to be a Rod, Staff, or Wand:

Enhanced Arcane Focus

Item: A rod, staff, or wand (requires attunement)

 RAI, I would expect it to work on any valid spellcasting focus.  Remember that these infusions can be given to other party members.  For an artificer, artisan tools are a valid focus

You must have a spellcasting focus—specifically thieves’ tools or some kind of artisan’s tool—in hand when you cast any spell with this Spellcasting feature (meaning the spell has an ‘M’ component when you cast it)

So I would allow Enhanced Arcane Focus on smiths tools etc.