Ke kalaiwa anaʻO ka hana ʻana i ka ingot kila i loko o ka billet me ka hāmare a i ʻole ka mīkini kaomi; E like me ka haku mele, hiki ke hoʻokaʻawale ʻia ke kila i ke kila kalapona a me ke kila kila.

(1) Ma waho aʻe o ka hao a me ke kalapona, ʻo ka hui kemika o ke kila kalapona kekahi mau mea e like me ka manganese silico, sulfur a me ka phosphorus, ma waena o ka sulfur a me ka phosphorus he mea haumia ʻino.ʻO Manganese silico kahi mea deoxidized i hoʻohui ʻia i ke kila kalapona i ke kaʻina hana kila.Wahi a ka ʻokoʻa kalapona ʻokoʻa i loko o ke kila kalapona, ua māhele pinepine ʻia i ʻekolu mau ʻano:
ʻO ke kila kalapona haʻahaʻa: ʻO 0.04% -0.25% ka nui o ka carbon;
Medium carbon steel: 0.25% -0.55% carbon content;
Ke kila kalapona kiʻekiʻe: ʻoi aku ka nui o ke kalapona ma mua o 0.55%
(2) Hoʻohui ʻia ke kila kila i hoʻokahi a ʻoi paha o nā mea hoʻohui i loko o ke kila kalapona a me ke kila maʻemaʻe e like me ke kila manganese alloy element a i ʻole nā ​​​​mea paʻa paʻa, aia pū kekahi mau mea hoʻohui, e like me ka nickel chromium molybdenum vanadium titanium tungsten cobalt aluminika zirconium niobium. a me ka laha 'ole o ka honua a pela aku. Eia kekahi, aia kekahi mau mea hao calcium i loko o ka boron a me ka nitrogen etc. Nonmetal elements e like me ka nui o ka huina o ka mea hao ma ke kila, ua maheleia i ekolu mau mahele.

ʻO ke kila kila haʻahaʻa: ʻoi aku ka liʻiliʻi o ka nui o nā mea hoʻohui i ka 3.5%;
ʻO ke kila kila kila:ʻo ka nui o nā mea i hoʻohuihuiʻia he 3.5-10%;
ʻO ke kila kila kiʻekiʻe: ʻoi aku ka nui o ka ʻike o ka mea hoʻohuihui ma mua o 10%
E like me ka helu o nā mea hoʻoheheʻe like ʻole i loko o ke kila kila, hiki ke hoʻokaʻawale ʻia i ke kila ternary a me nā mea hao he nui, e like me nā ʻano o nā mea hao i loko o ke kila, hiki ke hoʻokaʻawale ʻia i ke kila manganese, ke kila chromium, kila boron, kila silika, kila manganese, kila manganese chromium, kila molybdenum, chromium molybdenum, tungsten vanadium kila a pēlā aku.