Cold end core components. During the working process of the engine, the blades are affected by centrifugal force, aerodynamic force generated by air and gas, thermal stress, alternating force and random load, accounting for more than 30% of the workload of the whole engine manufacturing. Under the action of various loads, the blade is prone to high cycle fatigue and thermal fatigue. In order to ensure the work quality and efficiency, the material selection and production technology of the blade have high requirements
Engine blades can be divided into fan blades, compressor blades and turbine blades according to their location and function. Fan blades and compressor blades are cold end components, and turbine blades are hot end components.
Compressor blades can be divided into compressor rotor blades (working blades) and compressor stator blades (rectifier blades). Turbine blades can be divided into turbine working blades and turbine guide blades. The fan blade initially compresses the air entering the engine. The compressed gas is divided into two ways. One way enters the inner channel for continuous compression, and the other way enters the outer culvert for direct high-speed discharge to generate thrust.
The compressor blades further compress the air entering the inner channel, and the air pressure and temperature rise significantly to meet the needs of the combustion chamber. The turbine blade has the effect of expansion and pressure reduction, which can convert the chemical energy of gas into the mechanical energy of turbine.
The materials of blades include aluminum alloy, stainless steel, titanium alloy, superalloy and composite blades. Fan and compressor blades are cold end components with relatively low working temperature. Titanium alloy, superalloy and other materials are generally used. Titanium alloy is widely used in the production of compressor blades because of its low specific gravity, high specific strength and corrosion resistance.
In terms of manufacturing technology, the compressor blade is thin and easy to deform. Accurately controlling its forming accuracy and processing with high efficiency and quality are the core difficulties in the blade manufacturing process. Among all kinds of blades, compressor blade is one of the parts with the most complex surface structure and the most demanding working environment of aeroengine.
In order to reduce the power loss of the compressor blade, the thickness of the blade itself is thinner than that of other parts of the compressor blade. The complex torsion degree of the profile is embodied in the different bending and torsion angles of the profile from the blade root to the blade tip. On the other hand, the thickness of the front and rear edges of the blade is only 0.1-0.2mm, and the contour requirement is high.