A Method for Evaluation of Service Conditions of Superalloy Turbine Blades

Abstract

The invention provides a method for evaluating the service condition of a high-temperature alloy turbine blade and relates to the evaluation of the service condition of a DZ125 directional solidifiedhigh-temperature alloy turbine blade. According to the method, quantitative relations between a microstructure and service temperature, stress and time are established through machine learning on thebasis of a microstructure evolution database of DZ125 alloy under a near-service condition. The evaluation of the equivalent maximum service temperature and corresponding stress and time of the bladeis realized on the basis of the quantitative relations and the quantitative characterization results of the microstructure of the DZ125 alloy turbine blade. Compared with an existing laboratory simulation evaluation method, the method of the invention has higher accuracy and operability; meanwhile, the method of the invention is not influenced by boundary conditions, the method has higher reliability compared with a finite element simulation method. The method is suitable for engineering application and has relatively high engineering application significance and a bright prospect in the service temperature evaluation of DZ125 alloy and other single-crystal or directional alloy turbine blades.

Description

technical field [0001] The invention belongs to the technical field of nickel-based directional solidification superalloy blades, and in particular relates to a method for evaluating service conditions of directional solidification turbine blades. Background technique [0002] Aeroengines are highly complex and sophisticated thermodynamic machines. As one of the most critical components of aeroengines, turbine blades are important hot-end components that convert the enthalpy and kinetic energy of gas into mechanical energy. As the thrust-to-weight ratio of aero-engines continues to increase, the temperature of the gas outside the blades continues to increase, often far exceeding the melting point of the blade material. The measurement and calculation of the substrate temperature increase the difficulty. At the same time, the emergence of structures such as internal cooling holes makes the original complex service stress field of the blade more difficult to measure and calcu...

AI Technical Summary

Problems solved by technology

However, in the existing scheme, there are still the following points to be optimized: 1) The evaluation of the temperature and stress of the turbine blade is independent, the two methods are not unified, and the coupling effect of temperature and stress The consideration needs to be further deepened; 2) Both methods use the method of artificial comparison to obtain the evaluation results, which is easy to introduce subjective errors in this process, resulting in the failure to reach a high level of accuracy and operability; 3) In the existing In the method, when evaluating the equivalent maximum service temperature, the factors of the service history and damage time of each part of the turbine blade are not taken into account, which may lead to an increase in the evaluation error

In summary, the current experimental methods that quantify the degraded tissue and use it to quantitatively evaluate the actual service temperature of the blade are difficult to operate and have low precision, and are difficult to apply on a large scale

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