Tool made from carbon less effective muffling sound of impact (4,6)

'tool' is the definition.
(claw hammer is a kind of tool)

'carbon less effective muffling sound of impact' is the wordplay.
'carbon' becomes 'C' (C is the chemical symbol for carbon).
'less effective' becomes 'lamer' (lame can mean ineffective or feeble).
'muffling' means one lot of letters goes inside another.
'sound of impact' becomes 'wham' (I've seen this in another clue).
'lamer' placed around 'wham' is 'lawhammer'.
'c'+'lawhammer'='CLAW-HAMMER'

'made from' is the link.