Laboratory of Applied Physics and Mechanics of Advanced Materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
Key Laboratory of Interface Science and Engineering in Advanced Materials, Ministry of Education, Taiyuan University of Technology, Taiyuan, 030024, China.
Sci Rep. 2017 May 12;7(1):1877. doi: 10.1038/s41598-017-02100-9.
The present study demonstrates that Ti-based metallic glass matrix composites (MGMCs) with a normal composition of TiZrNiTaBe containing ductile dendrites dispersed in the glass matrix has been developed, and deformation mechanisms about the tensile property have been investigated by focusing on twinning-induced plasticity (TWIP) effect. The Ti-based MGMC has excellent tensile properties and pronounced tensile work-hardening capacity, with a yield strength of 1100 MPa and homogeneous elongation of 4%. The distinguished strain hardening is ascribed to the formation of deformation twinning within the dendrites. Twinning generated in the dendrites works as an obstacle for the rapid propagation of shear bands, and then, the localized necking is avoided, which ensures the ductility of such kinds of composites. Besides, a finite-element model (FEM) has been established to explain the TWIP effect which brings out a work-hardening behavior in the present MGMC instead of a localized strain concentration. According to the plasticity theory of traditional crystal materials and some new alloys, TWIP effect is mainly controlled by stacking fault energy (SFE), which has been analyzed intensively in the present MGMC.
本研究表明，已经开发出了具有正常成分 TiZrNiTaBe 的 Ti 基金属玻璃基复合材料 (MGMC)，其中含有分散在玻璃基体中的韧性枝晶，通过关注孪生诱导塑性 (TWIP) 效应研究了拉伸性能的变形机制。Ti 基 MGMC 具有优异的拉伸性能和显著的拉伸加工硬化能力，屈服强度为 1100 MPa，均匀伸长率为 4%。显著的应变硬化归因于枝晶内变形孪晶的形成。在枝晶中产生的孪晶作为剪切带快速传播的障碍，从而避免了局部颈缩，这确保了此类复合材料的延展性。此外，建立了有限元模型 (FEM) 来解释 TWIP 效应，该效应在本 MGMC 中产生了加工硬化行为，而不是局部应变集中。根据传统晶体材料和一些新型合金的塑性理论，TWIP 效应主要受层错能 (SFE) 控制，在本 MGMC 中对此进行了深入分析。
