Amorphous metallic alloys, which are often referred to as metallic glasses, are relatively new materials, mainly known in the form of thin ribbons. They are pre-pared from molten alloys by rapid quenching technique. In this technique the melt of a metallic alloy is poured onto rapidly rotating copper drum. Due to low thickness of the ribbon (20 to 30 micron) it is cooled at a very high rate (about million degrees per second). It prevents the crystalline structure from growing during solidification. During such a short time the crystalline structure has no chance to arise. Instead the amorphous solid in the form of a very thin ribbon like tape (width varies from few millimeters to 20 cm) is prepared.