Effects of Zn content on microstructures and mechanical properties of in-situ TiB2/Al-Zn-Mg-Cu composites subjected to hot extrusion
Effects of Zn content on microstructures and mechanical properties of in-situ TiB2/Al-Zn-Mg-Cu composites subjected to hot extrusion
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DOI：
10.1016/j.msea.2018.11.030
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发表时间：
2019-01
期刊：
影响因子：
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通讯作者：
M. Wang;Yan Wang;Jun Liu;Zhe Chen;Han Chen;Yi Wu;Fengguo Zhang;Haowei Wang
中科院分区：
文献类型：
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作者：
M. Wang;Yan Wang;Jun Liu;Zhe Chen;Han Chen;Yi Wu;Fengguo Zhang;Haowei Wang
研究了不同Zn含量（x = 6.9，9和12wt%）的原位TiB 2增强Al-xZn-2.5Mg-2.4Cu-0.15Zr复合材料的组织和力学性能。通过扫描电子显微镜和相关的取向成像显微镜进行了详细的微观结构研究。结果表明，随着Zn含量从6.9wt%增加到12wt%，由于TiB 2颗粒与Al基体之间的界面能降低，TiB 2颗粒严重团聚，分散程度明显提高。随着Zn含量的增加，挤压试样的平均晶粒尺寸减小，晶粒形状趋于等轴化，这是由于在晶粒中形成了LAGB并将其转变为HAGB，包围着分散的TiB 2颗粒。随着Zn含量从6.9%增加到12%，挤压试样的屈服强度从597 MPa提高到707 MPa，这主要是通过晶界强化和增强颗粒强化机制实现的。
Microstructures and mechanical properties of in-situ TiB2reinforced Al-xZn-2.5Mg-2.4Cu-0.15Zr composites with different Zn content (i.e. x = 6.9, 9 and 12 wt%) were studied in this work. Detailed microstructural investigations have been carried out via scanning electron microscopy and associated orientation imaging microscopy. The results indicate that as Zn content increased from 6.9 to 12 wt%, the severe clusters of TiB2particles were noticeably dispersed owing to the decreased interfacial energy between TiB2particles and Al matrix. The average grain size of extruded samples decreases and the grain shapes tend to be more equiaxed with the increase of Zn content, thanks to the formation of LAGBs and its transformation to HAGBs surrounding dispersed TiB2particles in the grain. In addition, the yield strength of extruded samples increases from 597 MPa to 707 MPa with the increase of Zn content from 6.9 to 12 wt%, via grain-boundary strengthening mechanism and reinforcing particles strengthening mechanism.