The technological scheme for producing a high-temperature layered composite material using solid-phase welding of a molybdenum foil package in a vacuum at a given temperature and load is presented. The diffusion welding mode allows preserving the positive properties of the original components to a large extent. The structure and fracture surface of the composite material are studied using electron microscopy. The non-uniform composite structure leads to increased energy dissipation during testing, which increases its crack resistance. Composite specimens in the form of rectangular rods were tested under three-point bending in the temperature range 20–1400°C. The load-deflection dependence is obtained, allowing qualitative estimation of the deformation characteristics of the specimens. The dependence of the composite material strength on temperature is also obtained. The strength values meet the requirements for materials of this kind and generally exceed the corresponding strength of known molybdenum alloys. The deformation diagrams of the specimens indicate the non-brittle nature of their fracture, which is confirmed by microscopy studies of the structures. The interfaces between the components act as brakes on crack propagation, increasing the resistance of the composite structure to complete destruction, along with plastic deformations of the foils in the zone of macrocrack propagation.
Kiiko et al. (Mon,) studied this question.