METHOD FOR THE CONTACTLESS, NON-DESTRUCTIVE DETERMINATION OF THE HARDNESS, POROSITY AND/OR MECHANICAL STRESSES OF MATERIALS OR COMPOSITE MATERIALS

摘要

Method for the contactless, destruction-free determination of the hardness, porosity and/or mechanical stresses of materials or composite materials using speckle photometry, in which coherent electromagnetic radiation is directed at a defined incidence angle onto a surface region of a structural component or a sample and the surface region illuminated by said radiation is imaged on an at least two-dimensional array of optical detectors and thermal and/or mechanical activation is carried out at a surface at the structural component or the sample at a distance from the irradiated surface region; wherein the array is used to detect in a temporally and spatially resolved manner the intensity of speckle electromagnetic radiation which is emitted as a result of the irradiation of the surface, and the speckle diffusivity is determined therefrom and then the respective hardness, porosity and/or mechanical stress is determined using the determined speckle diffusivity and reference values that were previously determined with other measurement methods for the respective material or material composite.