Effect of Ti element on the interfacial reactions and micro-structures of the Al-B4C composites fabricated by the stir-casting method

作者：Guo, Wenbo; Hu, Qiyao^*; Xiao, Peng; Deng, Yunqi

来源：Applied Surface Science, 2022, 584: 152619.

DOI：10.1016/j.apsusc.2022.152619

• Al-B4C composite
• Interfacial reaction
• Interfacial microstructure
• First principles

The effect of titanium (Ti) on the interfacial reactions and micro-structures of the Al-B4C composites were studied using theoretical calculations based on the first-principles approach of density functional theory in combination with experimental analysis. The experimental results showed that the addition of Ti caused a more uniform distribution of B4C particles and the disappearance of interfacial micro-cracks. Three interfacial reaction layers were formed on the surface of B4C particles, the inner layer was composed of Al3BC, the middle layer constituted fine-grained TiB2, and the outer layer consisted of coarse-grained TiB2. The thermodynamic analysis showed that the most favorable reaction paths in the Al-B4C and Al-Ti-B4C systems were 9Al + 2B(4)C & RARR; 2Al(3)BC + 3AlB(2) and 6Al + 3Ti + 2B(4)C & RARR; 2Al(3)BC + 3TiB(2), respectively. Finally, the formation mechanism of the interface reaction layers in Al-B4C and Al-Ti-B4C systems were discussed. The results indicated the inter-diffusion of interfacial atoms in the melt, atomic diffusion rate, atomic concentration, atomic size and lattice mismatch were the factors influencing the formation and growth of the B4C-Al3BC-TiB2 interface reaction layer.

• 单位
  南昌航空大学