Microstructure of joints Cu–Ta, Cu–Ti, Cu–Cu, produced by means of explosive welding: fractal description of interface relief

ABSTRACT

The paper studies the interface relief of copper–tantalum, copper–titanium and copper–copper joints. It demonstrates that interfaces could be considered as a fractal object. Fractal dimensions are calculated for these joints. A rule is established for the behavior of the fractal dimension during the transition from flat interfaces to wavy ones; this rule holds true of all joint pairs. Some behavior specifics are found for the fractal dimension of wavy interfaces of the copper–copper joint (which was substituted with Cu-Cu80Ni20 joint for convenience). The study shows that the fractal dimension in general decreases when welding modes are intensified. However, in the case of welding modes that are close in terms of energy input, certain peculiarities or deviations from such behavior can be observed.

Graphical Abstract

KEYWORDS:

• Explosive welding
• interface
• local melted zones
• fractals
• self-organization

Acknowledgments

The electron-microscopic investigations were performed at the Electron Microscopy Centre for Collective Use, Ural Branch, Russian Academy of Science. The work was performed under the State Task (theme “Pressure” no. АААА-А18-118020190104-3); project no. 18-10-2-24, Program of Ural Branch, RAS and also was supported in part by the Russian Foundation for Fundamental Investigations, project no. 20-42-660001.

Disclosure Statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Russian Foundation for Fundamental Investigations [20-42-660001].