Method for determining whether defects are present in the material of a ceramic component

A method for determining whether a defect is present in a ceramic component, the method comprising:

• determining a temperature difference between a first temperature and a second temperature based on an intended use of the ceramic component,
• bringing the ceramic component to the first temperature,
• after bringing the ceramic component to the first temperature, bringing the ceramic component to the second temperature,
• performing a resonance ultrasound spectroscopy on the ceramic component after bringing the ceramic component to the second temperature to produce an ultrasound spectrum of the ceramic component,
• comparing the ultrasound spectrum with a reference spectrum to determine a degree of similarity between the ultrasound spectrum and the reference spectrum,
• determining from the degree of similarity whether the defect is present in the ceramic component,
• evaluating the ultrasound spectrum to determine an actual value of an elastic constant of a material of the ceramic component,
• wherein the reference spectrum is determined based on an expected value of the elastic constant of the material of the ceramic component if the ceramic component were defect-free, and
• wherein the comparing includes comparing the actual value of the elastic constant of the material of the ceramic component with the expected value of the elastic constant of the material of the ceramic component.