Dyfrakcyjne stałe sprężystości materiałów polikrystalicznych

W pomiarach makronaprężeń metodami rentgenograficznymi stosuje się tzw. dyfrakcyjne stałe sprężystości, które można obliczyć według różnych modeli ciał sprężystych lub zmierzyć metodami rentgenograficznymi. Stosowane są różne modele ciał sprężystych: Voigta, Reussa, Hilla, Hubera i Schmida, Boasa, Bruggemana, Shibuya, Kneera i Kronera, Hashina i Shtrikmana, Kronera i Kocha, Laurenta i Eudiera, Aleksandrova, Ledbettera i Naimona. W pracy opisano zasady i warunki pomiarów stałych sprężystości materiałów polikrystalicznych i uzyskane rezultaty pomiarów.

---

X-ray elastic constants are used in macrostress measurement by X-ray methods. They can be calculated according to various models or measured by X-ray methods. There are presented possibilities to calculate X-ray elastic constants for various polycrystalline models of solid state with use of computer software. The models that were elaborated by Voigt, Reuss, Hill, Huber and Schmid, Boas, Bruggeman, Shibuya, Kneer and Kroner, Hashin and Shtrikman, Kroner and Koch, Laurent and Eudier, Kasprzak, Aleksandrov, Ledbetter and Naimon are taken into account. Calculation of shear modulus for copper is presented as an example. X-ray elastic constants for polycrystalline materials can be also measured by X-ray methods. There are described measurement method and original devices for bending or stretching of flat probes in counter goniometer. The special attention is paid to computer-aided calculations. Measured values of elastic constants for some polycrystalline materials are given.