Hoʻokaʻawale ʻia ke kila kila e like me ka hoʻohana ʻana i nā ʻano hana: ka hoʻoheheʻe ʻana i ke kila a me ka ʻoki ʻana i ke kila; Wahi a nā ʻano kiko, hiki ke hoʻokaʻawale ʻia i ʻelima mau ʻano: austenitic type, austenite-ferritic type, ferritic type, martensitic type a me precipitation-hardening type.