Tensile mechanical performance of Al/Ni dissimilar metals bonded by self-propagating exothermic reaction based on molecular dynamics simulation

To provide new possibilities for electrode materials, a new welding method of Al/Ni dissimilar metals was studied using molecular dynamics in this research. The effective bonding between aluminum and nickel was achieved by Al-Ni reactive nano-multilayers (RNMLs). The tensile strength of the bonded component was 57 % higher than that of diffusion-bonded Al/Ni nanowires. First, compared to the two single-crystal metals before bonding, the Young's modulus of the bonded component was 48.88 GPa higher than that of single-crystal aluminum and 68.09 GPa lower than that of single-crystal nickel. Furthermore, a large number of stair-rod dislocations and nano-coherent twins were generated in the process of tensile loading, improving the mechanical performance of the bonded component. Second, as the atomic ratio of Al-Ni RNMLs increased, the tensile strength decreased first to 6.22 GPa and then continuously increased to 7.48 GPa, and the Young's modulus increased from 113.73 to 141.73 GPa and remained stable. When the atomic ratio was 1.98, Shockley dislocations and stair-rod dislocations were more easily generated. Similarly, an ignition temperature of 830 K resulted in the highest tensile strength of the bonded components among all of the RNMLs ignition temperatures.