Ultrafast shape change and joining of small-volume materials using nanoscale electrical discharge

• Published in: Nano research Vol. 8; no. 7; pp. 2143 - 2151
• Main Authors: Wang, Cheng-Cai, Li, Qing-Jie, Chen, Liang, Cheng, Yong-Hong, Sun, Jun, Shan, Zhi-Wei, Li, Ju, Ma, Evan
• Format: Journal Article
• Language: English
• Published: Beijing Tsinghua University Press 01-07-2015; Springer Nature B.V
• Subjects: Atomic/Molecular Structure and Spectra; Biomedicine; Biotechnology; Chemistry and Materials Science; Condensed Matter Physics; Conduction cooling; Conduction heating; Copper; discharge; Dissipation; electrical; Evolution; glass; High strain rate; Joining; Materials Science; Mechanical properties; Melts; metal; metallic; nanoscale; Nanostructure; Nanotechnology; Research Article; Welding; United States > US; China; Massachusetts; metal; nanoscale; welding; electrical discharge; metallic glass
• ISSN: 1998-0124; 1998-0000
• DOI: 10.1007/s12274-014-0685-7

Using nanoscale electrical-discharge-induced rapid Joule heating, we developed a method for ultrafast shape change and joining of small-volume materials. Shape change is dominated by surface-tension-driven convection in the transient liquid melt, giving an extremely high strain rate of N106 s-1. In addition, the heat can be dissipated in small volumes within a few microseconds through thermal conduction, quenching the melt back to the solid state with cooling rates up to 108 K.s-1. We demonstrate that this approach can be utilized for the ultrafast welding of small-volume crystalline Mo （a refractory metal） and amorphous Cu49Zr51 without introducing obvious microstructural changes, distinguishing the process from bulk welding.