Investment casting is one of oldest casting techniques. Today it is used for very precise aerospace parts casting that require the highest engineering tolerances.

Made of INCONEL (nickel based alloy), the latest aircraft engine designs are targeted to bring down fuel consumption and make the engine more efficient. This type of casting requires complex cooling channels and inner cavities that don’t allow for the use of traditional ultrasonic non-destructive methods. CT is the only non-destructive method that can measure internal walls to identify any core shift that might happen during the casting process.

The dense material and shape of a modern HPT (high pressure turbine) blade makes it difficult to create high quality CT scans that show minimum grey value differences throughout the entire airfoil area and sharply defined edges – detail necessary to perform reliable measurements. The “Scroll” feature was developed to be able to share CT results on a non-proprietary object that simulates the problems of real HPT blades. This allows you to measure internal walls and concave and convex outer surfaces. It also allows calibrating the part using traditional measurement methods like tactile CMM.

Multiple scans of the same sample can provide good cumulative statistics to analyze the accuracy of the scan (standard uncertainty).