On the Hardness and Elastic Modulus of Phases in SiC-Reinforced Al Composite: Role of La and Ce Addition

Abstract

The use of silicon carbide particles (SiCp) as reinforcement in aluminium (Al)-based composites (Al/SiCp) can offer high hardness and high stiffness. The rare-earth elements like lanthanum (La) and cerium (Ce) and transition metals like nickel (Ni) and copper (Cu) were added into the matrix to form intermetallic phases; this is one way to improve the mechanical property of the composite at elevated temperatures. The α-Al15(Fe,Mn)3Si2, Al20(La,Ce)Ti2, and Al11(La,Ce)3, π-Al8FeMg3Si6 phases are formed. Nanoindentation was employed to measure the hardness and elastic modulus of the phases formed in the composite alloys. The rule of mixture was used to predict the modulus of the matrix alloys. The Halpin–Tsai model was applied to calculate the elastic modulus of the particle-reinforced composites. The transition metals (Ni and Cu) and rare-earth elements (La and Ce) determined a 5–15% increase of the elastic modulus of the matrix alloy. The SiC particles increased the elastic modulus of the matrix alloy by 10–15% in composite materials.

The Influence of Ce, La, and SiC Particles Addition on the Formability of an Al-Si-Cu-Mg-Fe SiCp-MMC

“…On the other hand, the addition of La and Ce to the matrix alloy determines a doubled peak stress, and this is due to the presence of hard phases dispersed in the matrix. As previously reported [ 21 , 22 ], the Al 11 (Ce,La) 3 and Al 20 (Ce,La)Ti 2 phases strengthen the matrix alloy significantly, giving 15% higher elastic modulus and 55% higher strength at 300 °C. The material can be considered a two-level composite: both the (La,Ce)-based phases and the SiC particles act as reinforcement.…”

“…The particle dispersion was uniform, and the addition of La and Ce to the matrix alloy did not change the transfer efficiency of SiC particles; hence the SiC fraction of the C0_23 and C1_23 alloy was similar. The generation of new phases in the C1_23 material, previously identified as ɑ-Al 15 (Fe,Mn) 3 Si 2 , Al 20 (La,Ce) 3 Ti 2 and Al 11 (La,Ce) 3 [ 22 ], did not alter particle addition and distribution.…”

“…The addition of transition metals [ 18 , 19 , 20 ] and rare earth elements [ 21 , 22 ] to the matrix alloy helps to improve the maximum operating temperature of the composite material. Several methods produce metal matrix composites [ 23 ], such as powder metallurgy, pressure infiltration, spray deposition, and stir casting.…”

On the Efficient Particle Dispersion and Transfer in the Fabrication of SiC-Particle-Reinforced Aluminum Matrix Composite

“…In previous works, La and Ce elements were added to the matrix alloy of Al-based MMCs to increase their mechanical resistance at high temperatures [22][23][24] for their use in train brake discs. The same composite materials were investigated in the present study from a process point of view to evaluate particle dispersion and transfer efficiency.…”

Characteristics of the Surface Topography and Tribological Properties of Reinforced Aluminum Matrix Composite

“…A review of the literature shows that there are many works presenting test results that have been obtained for different materials, including coatings and Aluminum Metal Matrix Composites. Most of the works concern the study of material properties, mechanical properties [ 18 , 19 , 20 ] and microstructure, and their influence on wear [ 20 , 21 , 22 , 23 , 24 , 25 ] (tribological characteristics—friction coefficient, wear traces). Usually, if a surface analysis is conducted, only profile roughness parameters (such as Ra or Rz) are checked, which is not enough to characterize the surface topography, a fact that the authors Brown et al [ 26 ], Leach [ 27 ], Niemczewska-Wójcik et al [ 28 ], and Whitehouse [ 29 ] have drawn attention to.…”