The study of the kinetics of interfacial reactions in metal matrix composites (MMCs) is of crucial importance for optimizing their mechanical properties and performance. In particular, QC-reinforced aluminum alloy MMCs have attracted considerable attention due to their combination of high strength, light weight, and improved wear resistance.
This paper is devoted to the study of the kinetics of the interphase reaction in a CMM obtained by powder metallurgy, where the matrix is aluminum alloy 6061, and the reinforcing element is a quasicrystalline alloy of nominal composition (Al63Cu25Fe12)99Ce1. Cerium (Ce) is introduced to improve wettability and reduce the surface tension between the quasicrystalline phase and the aluminum matrix.
The experimental studies were carried out using differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) with energy-dispersive X-ray analysis (EDS). The CMM samples were subjected to heat treatment in the temperature range from 500°C to 600°C with different holding times to study the evolution of the interphase boundary.
The DSC results showed the presence of endothermic peaks corresponding to diffusion-controlled processes occurring at the interface. The formation of intermetallic compounds such as AlxCuyFe z was observed near the surface of the quasicrystalline particles, which was confirmed by the SEM and EDS data. The kinetic parameters of the reaction, including the activation energy and pre-exponential factor, were determined using the Arrhenius model.
The obtained results allow optimizing the heat treatment parameters to control the formation of intermetallic phases and, consequently, improving the mechanical properties of quasicrystalline CMMs based on an aluminum matrix.
Aluminum matrix is a promising material with significant potential for further development. Hot pressing and sintering technology was used to obtain the particle-reinforced quasicrystalline composite material 6061. This composite based on aluminum matrix reinforced with (AlCu25Fe12)99Ce1 has outstanding properties and effective wetting of the interface. In the composite structure, diffusion processes of elements and microstructure in the contact zone between the reinforcing phase and the matrix were studied. The results showed that the interaction between the reinforcement and the matrix leads to the formation of the I phase, Cu9Al4 phase, Al23CuFe4 phase and ω phase. The Al13Ce2Cu13 phase is constantly present in the reinforcing phase, which provides a strong connection with the matrix. In parallel, the diffusion kinetics of the transition layer formed between the quasicrystalline phase and the matrix during hot pressing was analyzed. It has been established that the optimal thickness of the transition layer is 4.85 μm, which significantly affects the improvement of the properties of the composite material. Studies of the microstructure and dynamics of interphase boundaries in quasicrystalline composites 6061 with an aluminum matrix reinforced with (Al63Cu25Fe12)99Ce1 create a basis for the development of durable and high-strength materials with improved performance characteristics.
Author: Juan Wang, Zhong Yang, Liying Wang, Jianping Li
Institute:
School of Materials Science and Chemical Engineering, Xi’an University of Technology, Xi’an 710021, China/
Xi’an Tianli Metal Composite Material Co. Ltd., Xi’an 710299, China