Thawj yog tias lub zog yog ob peb lub sij hawm siab tshaj qhov uas zoo tib yam iav thiab nws yog ib qho uas ua rau tsis khov.
Qhov thib ob yog kev siv zoo, thiab nws qhov peev xwm ua haujlwm tau zoo dua qub los txhim kho lub zog tsis muaj zog. Txawm hais tias qhov iav tempered, nws yuav pom cov thauv me me uas tsis muaj ntse ces, thiab kev puas tsuaj rau tib neeg lub cev zoo heev. Cov iav tempered muaj zog tuaj yeem ua rau quenching thiab kub ceev tshaj qhov qub iav. Nws muaj kev txhim kho 3 ~ 5 zaug, thiab feem ntau muaj peev xwm tiv thaiv tau qhov kub hloov ntawm ntau tshaj 250 degrees, uas muaj kev pom tseeb los tiv thaiv thermal cracking. Nws yog ib qho ntawm kev nyab xeeb iav. Txhawm rau ua kom muaj kev ruaj ntseg ntawm cov khoom tsim nyog rau tsev siab.
