Njirimara nke mpịachi efere kwụ ọtọ CDH 1. Mwepụta ihe eji emepụta ọkọlọtọ maka ịwelite efere efere na akụkụ nchara. Usoro mkpọchi mkpọchi mkpọchi nke oge opupu ihe ubi na-emesi ike ike nke mbụ ike.
2. A na -ejikọ ihe nkedo nwere usoro nchekwa, na -ahụ na mgbachi ahụ anaghị amị amị mgbe etinyere ike yana mgbe eburu ibu.
3. A na -akpọchi mkpọchi akpọchi yana mepere emepe.
4. High frquency quenching nke die esorowo pụrụ iche alloy steels na -enye ukwuu anwụ ngwa ngwa ka cam.