In-situ investigation on tensile properties of a novel Ti/Al composite sheet
In-situ investigation on tensile properties of a novel Ti/Al composite sheet
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DOI：
10.1016/j.ijmecsci.2022.107592
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发表时间：
2022-08-05
影响因子：
7.3
通讯作者：
Jiang, Zhengyi
中科院分区：
文献类型：
--
作者：
Li, Zhou;Lin, Y. C.;Jiang, Zhengyi
层合/叠层复合材料可以提供组合组分金属的优点，但其异质微观结构在随后的再制造过程中表现出与均匀对应物不同的力学性能。采用原位测试技术研究了新型爆炸焊接复合材料TA 1/5083板材的拉伸性能、组织演变和变形行为。结果表明，在复合材料中形成了一个波浪形过渡区，在界面附近元素扩散和显微硬度呈现梯度。拉伸方向为45 °的滑移带主要发生在5083侧（而不是TA 1侧），变形量增加。尽管5083层中晶粒的位错密度显著增加，但这些晶粒沿拉伸方向沿着略微伸长，而没有显著的取向变化。在原位拉伸过程中出现了三个变形阶段和随后的裂纹萌生阶段。界面区微裂纹的萌生是由于界面波结构底部的内应力集中所致。一旦初始微裂纹演变成界面区的金属间化合物（IMC），TA 1和5083层的高应力集中程度导致颈缩和连续断裂。该研究可为工业用高质量Ti/Al复合材料构件的设计提供参考。
Laminated/bimetal composites can offer the advantage of combining constituent metals, but their heterogeneous microstructures exhibit different mechanical properties during subsequent remanufacturing process than those of the homogeneous counterparts. This study investigated the tensile properties, microstructural evolution and deformation behaviours of a new explosive welded TA1/5083 composite sheet using the in-situ characterisation. It is found that a wavy transition zone forms in the composite sheet, showing gradients in the element diffusion and micro-hardness adjacent to the interface. The slip bands with the tensile direction of 45 primarily occur in the 5083 side (rather than the TA1 side) with an increase in deformation. Although the dislocation density of the grains in the 5083 layer increases significantly, these grains are slightly elongated along the tensile direction without a significant orientation change. Three deformation stages and a subsequent crack initiation stage appear during the in-situ tensile process. The initiation of micro-cracks in the interfacial zone results from the internal stress concentration occurring at the bottom of interfacial wave structure. Once initial micro-cracks evolve into the intermetallic compounds (IMCs) of the interfacial zone, the high magnitude of stress concentrations of the TA1 and 5083 layers leads to necking and sequential fractures. This study can provide a reference for the design of high-quality Ti/Al composite components for industry.