Integral blade disc is the design of the engine rotor blade and disc as a whole, using a whole processing or welding (blade and disc material can be different) method of manufacturing, without processing mortise and groove. The advantages of this integral structure are as follows: the radial height and thickness of the blade rim and the size of the original tenon of the blade can be greatly reduced, and the weight reduction effect is obvious. The structure of engine rotor components is greatly simplified. The gas leakage loss in the gap between the tenon root of the split structure is eliminated. It avoids the malfunction caused by the fretting wear, crack and lock piece damage caused by the improper assembly of blade and wheel, which is conducive to improving the working efficiency of the engine and further improving the reliability.
Since the mid-1980s, the western developed countries have adopted the integral blade disc structure as the latest form of structure and aerodynamic layout in the design of new aero-engine. It represents the development direction of the fourth-generation and fifth-generation aero-engine technology with high thrust-to-weight ratio, and has become the necessary structure for engines with high thrust-to-weight ratio.
The integral blade disk structure is mainly used for fans and high-pressure compressor parts. The materials used for manufacturing integral disc are mainly
titanium alloy and nickel-based alloy. Titanium alloy materials are mainly used in the first few stages of fans and high-pressure compressor plates, while the latter several stages of high-pressure compressor plates are mostly nickel-based superalloy.
Numerical control milling (HSC), linear friction welding (LFW) and electrolytic machining (ECM) are the three major technologies of integral disc manufacturing.
