serva sakistumine
lehtmetalli sügavtõmbedefekt - sakkide moodustumine sügavtõmmatud tooriku/toote ülemises servas (vt sügavtõmbamine), the formation of ears or scalloped edges around the top of a drawn shell, resulting from directional differences in the plastic-working properties of rolled metal, with, across, or at angles to the direction of rolling (see: deep drawing)