In the present work, the porous Ti particle reinforced Mg-based bulk metallic glass matrix composites (BMGCs) have been successfully fabricated via a novel in-situ dealloying method in metallic melt. A dual reinforcing structure, including large-scale between porous particles and fine-scale inside one particle, was induced to further overcome the strength-plasticity tradeoff. The microstructure and mechanical properties of such dual-scale structure-reinforced BMGCs with various volume fractions and diameters of porous Ti particles were investigated in detail. It is found that with more and finer porous Ti particles, the BMGC showed both high fracture strength (1131.9 ± 39.1 MPa) and good plastic deformability (1.48 ± 0.38 %). The characteristic of the reinforcing structure (0.48 µm) inside the porous particles was close to the plastic processing zone size of the matrix (0.1∼0.2 µm), which generated a locally ideal reinforcing structure. Such dual-scale reinforcing structures with more interfaces can effectively promote the multiplication of shear bands at the interfaces. Due to the size effect, the refined submicron matrix between the Ti ligaments inside the porous particles should exhibit homogeneous shearing events. Such delocalization behavior from the dual-scale reinforcing structures should help to enhance the role of the interactions between shear bands, thus improving the yield strength of the composites. Based on the in-situ dealloying method, the dual-scale structure design provides a novel approach to fabricate various BMGCs with both high strength and good plasticity.

中文翻译：

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具有双尺度增强结构的原位多孔 Ti 颗粒增强 Mg-Cu-Gd 金属玻璃基复合材料的研制


在本工作中，通过一种新颖的金属熔体原位脱合金方法，成功制备了多孔 Ti 颗粒增强 Mg 基块状金属玻璃基复合材料 （BMGCs）。诱导双重增强结构，包括多孔颗粒之间的大尺度和一个颗粒内部的细尺度，以进一步克服强度-塑性权衡。详细研究了这种具有不同体积分数和直径的多孔 Ti 颗粒的双尺度结构增强 BMGCs 的微观结构和力学性能。研究发现，随着多孔 Ti 颗粒的增加和细小，BMGC 表现出较高的断裂强度 （1131.9 ± 39.1 MPa） 和良好的塑性变形能力 （1.48 ± 0.38 %）。多孔颗粒内部增强结构 （0.48 μm） 的特性接近基体的塑性加工区尺寸 （0.1∼0.2 μm），从而产生局部理想的增强结构。这种界面较多的双尺度加固结构可以有效促进界面处剪切带的倍增。由于尺寸效应，多孔颗粒内部 Ti 韧带之间的细化亚微米基质应表现出均匀的剪切事件。这种来自双尺度增强结构的离域行为应该有助于增强剪切带之间相互作用的作用，从而提高复合材料的屈服强度。基于原位脱合金方法，双尺度结构设计为制造各种具有高强度和良好塑性的 BMGC 提供了一种新颖的方法。