Method for preparing nanocarbide based on EB-PVD to reinforce matrix stability

Abstract

The invention discloses a method for preparing nanocarbide based on EB-PVD to reinforce matrix stability. An EB-PVD device is adopted for depositing a compact carbon film, in combination with diffusion treatment, carbon and a refractory element in the near-surface area of a single crystal high temperature alloy matrix are combined to in-situ generate the nanocarbide distributed in a dispersion manner, the refractory element is fixed in the matrix in a manner of the carbide, the loss speed of the refractory element in the matrix in the service process can be restrained, high-temperature structure stability of the matrix can be reinforced, and a secondary reaction zone (SRZ) in the service process can be prevented. The EB-PVD device is adopted for depositing a carbon film on the single-crystal matrix, pure carbon is adopted for serving as a carbon source, the difference of carbon activity in the diffusion process can be overcome, consistency of carbon activity is kept, other carburization processes can be avoided, the problem that in the chemical gas phase carburization process, gas components fluctuate or the carbon activity is not prone to control can be solved, and the carbide number, morphology, distribution and depth controllability can be improved.

Description

technical field [0001] The present invention relates to protective coating systems for blades in service at high temperatures. More specifically, the present invention relates to a method for preparing nano-carbides to enhance matrix stability based on EB-PVD. Background technique [0002] In a gas turbine engine, air is sucked into the engine, compressed by the compressor, mixed with fuel, and sent to the combustor for combustion. The gas flows through the turbine to drive the turbine to rotate to generate thrust. According to the service environment of turbine blades, it can be known that turbine blades will withstand complex loads such as high temperature, thermal cycle, thermal shock, oxidation, corrosion, and fatigue during service. In order to increase the thrust-to-weight ratio of an aero-engine, the most effective way at present is to increase the temperature of the combustion chamber of the aero-engine. Therefore, with the increasing requirements for the thrust-to...

AI Technical Summary

Problems solved by technology

[0011] The above three U.S. patents all use the chemical vapor phase carburizing method, which has some problems: the fluctuation of the carburizing gas composition makes it difficult to control the consistency of carbon activity, resulting in unstable carburizing results; there are many variables that need to be controlled, Increased variability of carburizing results; carrier gas for vapor-phase carburizing is toxic and explosive

The patent uses C 10 h 8 or C 14 h 14 There are certain problems as a target material: the target material needs to go through the process of chemical decomposition and deposition during deposition, and the chemical decomposition process is difficult to achieve precise control, resulting in fluctuations in the composition of the carbon source, and because the boiling point of this target material is very low , when the electron beam scans to the target, rapid gasification or even splashing will occur, and the process stability is poor

Images