The Influence of TiC and TiB2 Reinforcement on the Properties and Structure of Aluminum Alloy AMg2

The paper presents the results of research devoted to studying the effect of the type of reinforcing phase on the structure and properties of an aluminum matrix composite material (AMCM) obtained by the method of self-propagating high-temperature synthesis (SHS) in a melt. In the course of the research, an analysis is carried out and a choice is made to use titanium carbide and titanium diboride as reinforcing phases. During the experimental synthesis of SHS in the melt, AMg2–10% TiC and AMg2–10% TiB2 composite materials are obtained. In the course of further studies, microstructural, micro-X-ray spectral, and X‑ray phase analyses have been carried out, according to the results of which it is revealed that the technology used leads to the formation of the target TiC phase in the AMg2–10% TiC composite and TiB2, Al3Ti phases in the AMg2–10% TiB2 composite. On synthesized samples of composite materials, an assessment is made of physical and mechanical characteristics: hardness, porosity, and electrical conductivity. It is found that the hardness of AMCM obtained by the SHS method based on the AMg2 industrial alloy reinforced with titanium carbide is higher than the hardness of AMCM reinforced with titanium diboride by 44 MPa. Also, the porosity of the AMg2–10% TiC composite is lower than that of the AMg2–10% TiB2 composite by 6%. This paper also shows the effect of heat treatment on the physical and mechanical properties of AMg2–10% TiC and AMg2–10% TiB2 composite materials. Carrying out additional heating leads to an increase in the hardness values of composite materials, as well as a decrease in porosity. According to the results of a complex of studies, the use of titanium carbide is recommended as a reinforcing phase.