tempered vs hardened

tempered and hardened both are adjectives.

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

As adjectives, tempered and hardened are synonyms defined as:

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

Other synonyms of tempered include toughened, treated.

tempered (adjective)	hardened (adjective)
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	protected against attack (especially by nuclear weapons)
	made tough by habitual exposure
	converted to solid form (as concrete)
	used of persons; emotionally hardened