Hlau - iav tsis tsuas yog muaj qhov zoo ntawm cov hlau thiab iav, tab sis kuj kov yeej lawv qhov tsis zoo. Piv txwv li, iav yog tsis yooj yim sua thiab tsis muaj ductility. Lub zog ntawm cov iav hlau yog siab dua li ntawm cov hlau, qhov hardness siab tshaj qhov siab ntawm - hardness tool steel, thiab nws muaj qee qhov toughness thiab rigidity.
