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The selection of the necessary and sufficient number of Duralumin samples in determining the surface energy of metal aviation components is considered. The surface energy is determined by measuring the contact potential difference, which depends on the electron work function for the samples. The number of samples for measuring the contact potential difference must be no less than five.
An analytical model of the spectrum of thermally stimulated surface plasmon polaritons (TSSPPs) coming to the edge of a linear conducting sample has been developed. It has been found that the spectrum of such TSSPPs obeys neither the Wien law nor the Stefan–Boltzmann law for thermal radiation. The maximum of this spectrum is shifted to the low-frequency region with respect to the spectrum of the absolutely black body, and the magnitude of the shift is proportional to the sample length. The plasmon nature of the intensity increment of thermal radiation from the edge of a plane face of a duralumin sample has been verified experimentally. It has been shown that the intensity and spectrum of this increment can be controlled both by the sample temperature and by the extension of the face.
The effect of cyclic loading on the magnitude of coherent scattering regions (CSR) of X-ray radiation and microstresses of the II type in various crystalline materials: semiconductor (samarium sulfide) and metal (steel, duralumin) has been found. The loading was carried out by compressing the samples in various ways: all-round, uniaxial, bending compression. It is shown that with an increase in the number of compression cycles, the CSR values in all cases decrease, and the microstresses increase. These values can serve as parameters to assess the degree of mechanical fatigue of the material.