Microstructural characterization of ball-milled metal matrix nanocomposites (Cr, Ni, Ti)-25 wt% (Al₂O_3np, SiC_np)

Abstract

The microstructure of high-temperature metals such as Ti, Ni, and Cr can be modified using ceramic nanoparticles to form metal matrix nanocomposites (MMNCs). Such materials are generally prepared via powder metallurgy routes. In this study, 25 wt. % SiCnp and Al2O3np were separately ball-milled as a reinforcement of Ti, Cr, and Ni matrices to investigate their effects on the phase formation and morphology of the MMNCs. The XRD, SEM, and FESEM results indicated that the alumina-metal system could not be thermodynamically stable in a high-energy ball mill, while the SiC reinforcement could be retained and milled with the metals even after 24 hours. It was further observed that the distribution of nanoparticles was not affected by the type of metal, ceramic, and milling time. Finally, it was determined that the nanoparticles significantly reduced the average particle size of composite powders.

Study of the AISI 52100 Steel Reuse Through the Powder Metallurgy Route Using High Energy Ball Milling

“…The submicrometer particles of alumina are considered incoherent precipitates that can inhibit the grain growth during the thermal treatment, when located in the grain boundaries 9,21,22 . In general, the authors [10][11][12][16][17][18][19] also observed that, increasing the milling times, the properties of the MMCs composed by a metallic matrix and alumina as reinforcement achieved better results of density, porosity, hardness and elastic modulus, due to the factors discussed during this work.…”

“…It happens due to the small percentage of alumina that was added to the powder. Other authors as [10][11][12]16,18,19 also investigated the effect that extending the milling times generates in the crystalline structure of MMCs composed by metallic powders and alumina. The studies attested that, by increasing the milling times, the amorphization phenomena continued to happens.…”

“…Although the use of ceramic nanoparticles to reinforce metallic matrix is desirable, these particles present a tendency to agglomerate and form clusters, which is considered a problem. Thus, it is always indicated to control the granulometry of the powders before sintering 16 . Althought several authors in the literature studied the microstructural and mechanical properties of metal-matrix composites produced through the powder metallurgy route using high energy ball milling [10][11][12][16][17][18][19] , specific researches about the AISI 52100 steel with alumina additions were not found.…”

The Effect of Cu-Substitution on the Microstructure and Magnetic Properties of Fe-15%Ni alloy Prepared by Mechanical Alloying

“…As a result of the increased amount of cold working, the number of crystal defects (dislocation, vacancies, grain boundaries, stacking faults, etc.) increases with time and thus diffusivity of solute elements increases [38]. This leads to an increment in the defects and dislocations density which reduces the activation energy for diffusion.…”

Ball Milling Produced FeF3‐Containing Nanothermites: Investigations of Its Thermal and Inflaming Properties

“…Ball milling process is a typical combination of physical and chemical method to prepare nanothermites, in which particle sizes are affected by mechanical forces, and thus becomes a facile, cost‐effective and massive productive method. So far, massive researchers have applied this method on the mixing of aluminum and metal oxides.…”