TY - JOUR

T1 - Achieving Superior Strength-ductility-conductivity Combination in TiB2p 6201 Composites via Particle Rotation and Sub-grain Refinement

AU - Zhao, Kai

AU - Li, Xinchen

AU - Liu, Xiangting

AU - Shi, Shuyan

AU - Guo, Enyu

AU - Kang, Huijun

AU - Hao, Zhigang

AU - LI, Jiehua

AU - Zhang, Yubo

AU - Chen, Zongning

AU - Wang, Tongmin

PY - 2024/7

Y1 - 2024/7

N2 - The key factor in the material design of overhead power transmission lines is to obtain a desired balance among strength, ductility, and electrical conductivity. Herein, TiB2 particulate-reinforced aluminum matrix composites are prepared to find a way out of the intrinsic dilemma behind this balance by tailoring the subgrain refinement. The interaction in the form of inhomogeneous deformation induced by the flexibility discrepancy between the rigid particles and soft matrix is studied. On the one hand, the hexagonal plate-like TiB2 particles rotate with the inhomogeneous deformation, forcing the biggest exposed plane ((0001) basal plane) parallel to the plastic flow direction, which is beneficial for the dislocation multiplication and hindrance of dislocation slipping. On the other hand, inhomogeneous deformation generates plentiful geometry necessary dislocations and divides the microstructure into two types: in the particle-rich region ultrafine grains are formed and in the particle-free region significant subgrains refinement is observed. The subgrains with 3 wt% TiB2 are refined from ≈897 to ≈248 nm. Thanks to these microstructural benefits, the composites achieve the following strength–ductility–conductivity combination: ultimate tensile strength is 370 MPa, elongation after fracture is 11.2%, and electrical conductivity is 51.79% IACS. Besides, the elastic modulus reaches 75.43 GPa.

AB - The key factor in the material design of overhead power transmission lines is to obtain a desired balance among strength, ductility, and electrical conductivity. Herein, TiB2 particulate-reinforced aluminum matrix composites are prepared to find a way out of the intrinsic dilemma behind this balance by tailoring the subgrain refinement. The interaction in the form of inhomogeneous deformation induced by the flexibility discrepancy between the rigid particles and soft matrix is studied. On the one hand, the hexagonal plate-like TiB2 particles rotate with the inhomogeneous deformation, forcing the biggest exposed plane ((0001) basal plane) parallel to the plastic flow direction, which is beneficial for the dislocation multiplication and hindrance of dislocation slipping. On the other hand, inhomogeneous deformation generates plentiful geometry necessary dislocations and divides the microstructure into two types: in the particle-rich region ultrafine grains are formed and in the particle-free region significant subgrains refinement is observed. The subgrains with 3 wt% TiB2 are refined from ≈897 to ≈248 nm. Thanks to these microstructural benefits, the composites achieve the following strength–ductility–conductivity combination: ultimate tensile strength is 370 MPa, elongation after fracture is 11.2%, and electrical conductivity is 51.79% IACS. Besides, the elastic modulus reaches 75.43 GPa.

U2 - 10.1002/adem.202400531

DO - 10.1002/adem.202400531

M3 - Article

VL - 26.2024

JO - Advanced engineering materials

JF - Advanced engineering materials

SN - 1527-2648

IS - 13

M1 - 2400531

ER -