a method used to determine sheet metal properties, in particular the ductility of sheet metals by straining the clamped specimen with a hemispherical die until break (see: cupping test), lehtmetalli venitavuskatse, mis seisneb kinnitatud tooriku poolsfääri kujulise templiga deformeerimises prao moodustumiseni (purunemiseni) (vt venitavuskatse/venitatavuskatse)