Abstract: The defective cast blades blanks of K6 alloy are examined by means of optical, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spetrum (EDS). The results show that the main reason of discarded blades is the existence of non-metallic inclusions in cast K6 alloy getting into cast blades blanks in process of casting mould. Therefore, it is necessary to control the quality of raw and processed materials of K6 alloy and to select suitable technological parameters for melting and casting.