Effect of La on microstructures and mechanical properties of Cu/Ti₃SiC₂/C nanocomposites sintered by vacuum hot-pressing and hot isostatic pressing

Abstract

Researches have shown that the addition of trace amounts of rare earth element lanthanum (La) to the alloys and composites can significantly improve their microstructure and properties. In this work, Cu/Ti 3 SiC 2 /C composites with 0.05wt%, 0.1wt% and 0.3wt% La were prepared by powder metallurgy methodthrough mechanical alloying, hot-pressing (HP) and hot isostatic pressing (HIP). The effects of different La contents on the microstructure and mechanical properties of Cu/Ti 3 SiC 2 /C composites were investigated. The results show that La has a refinement effect on the grain of the matrix, and with the increase of La content, the size of the matrix of the composite becomes smaller. As the content of La increases, the performance of the composite exhibits a tendency to increase first and then decrease. The composite of 0.1wt% La exhibited the best performance with a hardness of 97.8 MPa, a tensile strength of 174.9 MPa, and a compressive strength and shear strength of 461.1 MPa and 102.1 MPa, respectively. Since the dimple is observed, the tensile fracture indicates that the fracture mode is a ductile fracture. The enhancement mechanism of La mainly includes dispersion strengthening and fine grain strengthening.

Hot Deformation Behavior and Processing Maps of ZnSnO3/Cu Composites

“…The results signify that the dislocation movement and DRX of ZnSnO 3 /Cu were more prone to occur in the composite. Additionally, it can also be deduced that trace Zr (0.56 wt.%) and La (0.005 wt.%) elements in the composite played important roles in the refinement of grain size according to the previous study [ 47 , 48 ], which was supposed to accelerate the dynamic recrystallization of the composites. These aspects contribute to good hot workability of the designed composites.…”

Research Progress in Interfacial Characteristics and Strengthening Mechanisms of Rare Earth Metal Oxide-Reinforced Copper Matrix Composites

“…Zhang et al discussed the influence of rare earth oxide Sc 2 O 3 addition to copper/diamond composites and found that it refined the microstructure of the matrix [ 18 ]. Lv et al studied the influence of elemental La on the microstructure and properties of Cu/Ti 3 SiC 2 /C nanocomposites [ 33 ]. They found that La has a refining effect on the matrix grain, and the matrix grain size decreases with increased La content [ 33 ].…”

“…Lv et al studied the influence of elemental La on the microstructure and properties of Cu/Ti 3 SiC 2 /C nanocomposites [ 33 ]. They found that La has a refining effect on the matrix grain, and the matrix grain size decreases with increased La content [ 33 ]. With increased La content, the properties of the composites showed a trend of first increasing and then decreasing.…”

“…With increased La content, the properties of the composites showed a trend of first increasing and then decreasing. The composites with 0.1 wt.% La showed the best properties, with tensile strength of 174.9 Mpa and shear strength and compressive strength of 102.1 Mpa and 461.1 MPa, respectively [ 33 ]. Because dimples were observed, the tensile fracture indicates the fracture mode is ductile fracture.…”

“…Because dimples were observed, the tensile fracture indicates the fracture mode is ductile fracture. The enhancement mechanism of La mainly includes dispersion strengthening and fine-grain strengthening [ 33 ]. Shu et al prepared multi-walled carbon nanotubes (MWCNTs) and graphene co-reinforced Cu–graphite composites with La by powder metallurgy and evaluated their mechanical properties [ 34 ].…”