Strain control type tensile-torsion thermal mechanical fatigue testing method

Abstract

The invention discloses a strain control type tensile-torsion thermal mechanical fatigue testing method, and relates to the technical field of testing of thermal mechanical fatigue property of material. The method comprises the following steps of (1) determining a heat strain compensation function under zero mechanical load; (2) setting the load parameters of the tensile-torsion thermal mechanicalfatigue testing; (3) applying two temperature cycles under the zero mechanical load; (4) applying the setting temperature and mechanical load; (5) recording the testing data; (6) according to the failure judgment reference or the preset cycle number, finishing the testing. The method has the advantages that the shearing strain is not changed along with the change of temperature; the applying of torsion heat strain compensation on a sample is not considered; the method can be used for testing the thermal mechanical fatigue property of the material, the design cost is reduced, and the design level is improved.

Description

technical field [0001] The invention belongs to the technical field of material thermomechanical fatigue performance testing, in particular to a strain-controlled tension-torsion thermomechanical fatigue test method. Background technique [0002] Hypersonic critical space vehicles, aero engines, gas turbines, nuclear power plants, power plants, and pressure vessels are subjected to extremely harsh service environments. Especially in the process of start-up, shutdown and rapid operation, the high-temperature parts of the above equipment not only bear mechanical cyclic loading, but also bear temperature cyclic loading at the same time, which can be called thermomechanical fatigue. The thermomechanical fatigue failure of key components is the main reason for the failure of the above equipment, and the sudden fatigue failure will cause immeasurable casualties and economic losses. [0003] At present, there is no systematic understanding of the damage mechanism of materials unde...

AI Technical Summary

Problems solved by technology

The thermomechanical fatigue failure of key components is the main reason for the failure of the above equipment, and the sudden fatigue failure will cause incalculable casualties and economic losses

[0003] At present, there is no systematic understanding of the damage mechanism of materials under thermomechanical fatigue loading, which is not conducive to the optimal design of equipment fatigue life and structure

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