In the present work

two types of single crystal (SC) blades using second generation superalloys DD5 were directionally solidified under industrial conditions. As one of the important material properties

the vibration frequency of the blades were measured and analyzed. It was found that clearly higher vibration frequency was exhibited in the blades with larger primary orientation deviation. In comparison

it was little affected by secondary orientation deviation. Another important factor influencing the vibration frequency is the airfoil constitution

instead of the total weight of a blade. In order to strictly control the blade vibration frequency

the airfoil constitution should be further optimized in the design

and the deviation of the primary crystal orientation of the blades should be minimized during the casting process.