本团队博士生刘孝淇等在International Journal of Mechanical Sciences发表研究论文。

摘要：Scaling metallic glasses (MGs) into bulk structural components remains a long-standing manufacturing challenge. Diffusion bonding offers a promising route, yet conventional diffusion bonding (CDB) requires prolonged thermal exposure that degrades the amorphous structure, while surface oxide films further impede interfacial healing. Here, rapid joining of a Zr-based bulk MG is achieved within minutes at nominal temperatures of 295–370 °C via pulsed current-assisted diffusion bonding (PCDB), and a controlled comparison using the same apparatus in a CDB configuration provides a basis for evaluating the thermal contribution and identifying additional current-associated effects. The joints exhibit higher shear strength than their CDB counterparts. Thermal-field simulations rationalize the high bonding efficiency of PCDB at the macroscopic scale, while quasi-in situ bonding and pre-oxidation experiments uncover the microscopic bonding mechanism, a competition between two current-mediated pathways in which current constriction at sparse asperity contacts is proposed to promote localized plastic flow that nucleates mechanical interlocking and fragments rigid oxide films, whereas the relatively smooth condition favors more spatially distributed metallurgical bonding; this competition in turn accounts for the experimentally observed roughness dependence of the joint strength, which departs from conventional expectations. Dynamic relaxation analysis further provides evidence for an additional current-associated contribution, whereby the pulsed current is associated with enhanced atomic-scale structural fluctuations, partially counteracting thermally induced mobility loss, and a qualitative free-volume framework is proposed to interpret changes in effective atomic mobility. This work elucidates the coupled thermal and current-associated mechanisms underlying PCDB, offering an efficient joining strategy for MGs.