Cov hlau uas siv ntau rau kev ua cov iav siv hauv kev tsim kho yog cov hlau quenched thiab tempered, hlau hardened, hlau carburized thiab hardened thiab hlau nitrided. Lub zog ntawm cov iav hlau cam khwb cia yog qis dua me ntsis ntawm cov iav hlau forged, thiab nws feem ntau siv rau cov iav loj, hlau grey cam khwb cia muaj cov khoom siv tsis zoo thiab tuaj yeem siv rau hauv kev sib kis iav qhib lub teeb, hlau ductile tuaj yeem hloov pauv hlau los ua cov iav.
Yav tom ntej, cov iav siv hauv kev tsim kho tab tom txhim kho mus rau hauv kev thauj khoom hnyav, kev kub ceev, kev raug siab thiab kev ua haujlwm zoo heev, thiab siv zog ua kom me me, lub teeb yuag, lub neej ntev thiab kev ntseeg siab ntawm kev lag luam.