Functionally oriented heat-resistant composites

Abstract

The developed technology for the production of surface composite materials, including high-energy mechanical processing, HVOF in a protective atmosphere, subsequent thermomechanical and thermal treatment of ZrCuNiCoTi and cBNNi3AlSiCCoY layers in a protective atmosphere, made it possible to increase the adhesive strength of the surface composite, reduce the porosity of composites, and improve the functional and operational properties of composite materials. Step-by-step methods of heat treatment and plastic deformation of surface layers have been developed to help stabilize the structure of materials while reducing residual stresses. Based on complex X-ray diffraction and electron microscopy studies, the structural parameters of surface composites have been determined. It is shown that the ZrCuNiCoTi alloy, located in the austenitic-martensitic state, has a nanocrystalline structure with a grain size of 80-120 nm, and the cBNNi3AlSiCCoY alloy consists of many intermetallic phases and inclusions, and has a nanoscale structure with a grain size of 100-200 nm. The microhardness of the surface layers of the ZrCuNiCoTi – cBNNi3AlSiCCoY composite was studied, which showed that the use of thermomechanical treatment leads to an increase in microhardness. As a result of statistical processing of experimental data, empirical mathematical dependences of the voltage amplitude on cyclic durability have been compiled. Mechanical tests of AISI 321H – NiCoTiZrHf – cBNCoMo, AISI 321H – ZrCuNiCoTi – cBNNi3AlSiCCoY, and AISI 321H – TiNiZrHfCoCu – cBNCoNiAlY composites for multi-cycle fatigue during bending with rotation were performed, showing that the AISI 321H+ ZrCuNiCoTi – cBNNi3AlSiCCoY composite has the highest cyclic durability.