Hardened, Queen gets new deal (8)
I believe the answer is:
annealed
'hardened' is the definition.
('annealed' can be similar in meaning to 'hardened')
'queen gets new deal' is the wordplay.
'queen' becomes 'anne' (I've seen this before**).
'gets' is a charade indicator (letters next to each other).
'new' is an anagram indicator.
'deal' with letters rearranged gives 'aled'.
'anne'+'aled'='ANNEALED'
(Other definitions for annealed that I've seen before include "Strengthened" , "made tougher" , "Like heat-treated metal" .)