Effect of electroshock treatment on microstructure evolution of Ti-6Al-4V/Cu-Cr-Zr interface fabricated by laser melting deposition

Abstract

This study aims to examine the effect of electroshock treatment (EST) on Ti-6Al-4V/Cu-Cr-Zr manufactured by laser melting deposition and explore the microstructure and mechanical properties to investigate the microstructure evolution of copper-based rail composite materials under high-energy-density currents. The results indicated that EST could promote atomic diffusion, enabling rapid preferential growth of TiCu in the metallurgical bonding zone. An increase of the current density promoted the nucleation of the primary Ti2Cu phase induced by the thermal effect of EST, which led to Cu solute enrichment and composition undercooling. Moreover, EST significantly improved nucleation rate and grain boundary migration. The average β grain size of the EST-1 sample increased from 2.83 μm to 3.62 μm, approximately, while the typical basic texture of EST-1 was enhanced. In EST-1, the shear strength of Ti-6Al-4V/Cu-Cr-Zr was 132 MPa, which was 65% higher than that of the original Ti-6Al-4V/Cu-Cr-Zr composite. The improvement in shear strength can be attributed to intergranular nano-precipitation and the improved wettability of Ti-6Al-4V/Cu-Cr-Zr. This work provides valuable insights into the preparation of high-value, high-performance Cu-based composites.

Keywords

Electroshock treatment / Ti-6Al-4V/Cu-Cr-Zr interface / Microstructure evolution / Mechanical properties

Acknowledgments

None.

Funding

This work was financially supported by the Major Research Plan of the National Natural Science Foundation of China (Grant No. 92266102), the National Natural Science Foundation of China (Grant No. 52271135, No. 52433026, No. 52571177), the Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal Materials (GFST2024KF05), and the Innovative Research Group Project of Hubei Provincial Natural Science Foundation (Grant No. 2025AFA014).

Conflict of interest

The authors declare they have no competing interests.

Author contributions

Conceptualization: Shiqiang Xie, Changlin Huang

Data curation: Shiqiang Xie, Changlin Huang, Jiawei Gong

Formal analysis: Shiqiang Xie, Jiawei Gong, Pei Wang, Lechun Xie

Funding acquisition: Lechun Xie

Investigation: Changlin Huang, Jiawei Gong

Methodology: Shiqiang Xie, Changlin Huang, Jiawei Gong

Project administration: Lechun Xie

Software: Shiqiang Xie, Pei Wang

Supervision: Yan Wen

Validation: Changlin Huang, Pei Wang

Writing - original draft: Shiqiang Xie, Changlin Huang Writing - review & editing: Yan Wen, Lechun Xie

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Availability of data

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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