toughened vs tempered

toughened and tempered both are adjectives.

Word	Noun	Adjective	Verb	Adverb
toughened	No	Yes	No	No
tempered	No	Yes	No	No

As adjectives, toughened and tempered are synonyms defined as:

toughened and tempered: made hard or flexible or resilient especially by heat treatment

Other synonyms of toughened include hardened, treated.

toughened (adjective)	tempered (adjective)
physically toughened	adjusted or attuned by adding a counterbalancing element
made hard or flexible or resilient especially by heat treatment	made hard or flexible or resilient especially by heat treatment