Method for testing biaxial strength of thermal barrier coating

Abstract

The invention discloses a method for testing biaxial strength of a thermal barrier coating. The method comprises the following steps of: (1) measuring thickness t, radius R, elasticity modulus E and poisson ratio v of each layer of a thermal barrier coating disc test piece, placing three test piece support parts at the periphery on the ceramic layer side on the bottom of the thermal barrier coating disc test piece in a symmetric distribution manner along the symmetric center of the thermal barrier coating disc test piece, and measuring the distance from a support point to the symmetric center of the thermal barrier coating disc test piece; (2) placing a loading point of a loading pressure head of a piston loading device on the surface on the base side on the upper part of the thermal barrier coating disc test piece in such a manner that the center of the loading pressure head is superposed with the center of the thermal barrier coating disc test piece, applying loads on the thermal barrier coating disc test piece until an initial break occurs at the center region on the surface of the ceramic layer, and recording the loading force Pcr at the time; and (3) calculating the biaxial tensile strength S of the thermal barrier coating disc test piece according to the loading force Pcr. The method provided by the invention can test the biaxial strength of the tested coasting simply and effectively, thereby laying the foundation for design and development of an efficient coating system.

Description

technical field [0001] The invention relates to the field of testing the strength of thermal barrier coatings, in particular to a method for testing the biaxial strength of thermal barrier coatings. Background technique [0002] Gas turbines and aero engines are important equipment for national defense and national production and construction. Improving their work efficiency is of great practical significance for saving energy and protecting the environment. Improving the internal gas temperature has become the most effective way to improve its working efficiency at present. As an effective thermal protection device, the thermal barrier coating system can be used on hot-end components such as turbine blades to greatly increase the temperature tolerance of these components. Due to the high brittleness of the surface ceramics in this system, its tensile strength is a parameter of great concern in engineering design. In the actual service environment, the coating is mainly su...

AI Technical Summary

Problems solved by technology

In the current strength test, uniaxial tension and three (four) point bending tests are basically used. These tests can only simulate the uniaxial stress state, so only the uniaxial strength can be measured.

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