Microstructure and Mechanical Properties of 45 vol.% SiCp/7075Al Composite
Microstructure and Mechanical Properties of 45 vol.% SiCp/7075Al Composite
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DOI：
10.1016/j.jmst.2015.01.012
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发表时间：
2015-09
影响因子：
10.9
通讯作者：
Z. Xiu;Wenshu Yang;Ronghua Dong;M. Hussain;Longtao Jiang;Yongxing Liu;Gaohui Wu
中科院分区：
文献类型：
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作者：
Z. Xiu;Wenshu Yang;Ronghua Dong;M. Hussain;Longtao Jiang;Yongxing Liu;Gaohui Wu
高体积含量SiCp/7 xxxAl复合材料的显微组织和力学行为尚未得到研究。因此，在本工作中，45体积%采用压力浸渗法制备了SiCp/7075 Al复合材料。经水淬和时效处理后的SiCp/7075 Al复合材料中，在SiC/Al界面附近发现了高密度位错。时效处理后，合金中出现了细小弥散的纳米η′相。与其它压力浸渗法制备的SiCp/Al复合材料不同的是，在SiC颗粒与Al基体之间存在一个界面层。此外，高分辨率透射电子显微镜（HRTEM）观察表明，该界面层是相干/半相干的SiC颗粒。45体积% SiCp/7075 Al复合材料具有较高的抗拉强度（630 MPa）和微塑性。与时效SiCp/2024 Al复合材料相比，时效SiCp/7075 Al复合材料的拉伸应变和抗拉强度分别提高了约200%和90%。Al基体中的纳米η′相对SiCp/7075 Al复合材料的强化效果有显著贡献，而SiC/Al基体间的界面层对SiCp/7075 Al复合材料的强度和塑性有利。
Microstructure and mechanical behavior of high volume content SiCp/7xxxAl composites have not been explored yet. Therefore, in the present work, 45 vol.% SiCp/7075Al composite has been prepared by pressure infiltration method. High density dislocations were found around SiC/Al interface in SiCp/7075Al composite after water-quenching and aging treatment. Fine dispersed nano-η′ phases were observed after the aging treatment. Adverse to other SiCp/Al composites prepared by the pressure infiltration method, an interface layer was observed between SiC particles and Al matrix. Furthermore, high-resolution transmission electron microscopy (HRTEM) observation indicated that this interface layer was coherent/semi-coherent with that of the SiC particles. 45 vol.% SiCp/7075Al composite demonstrated high tensile strength (630 MPa) and micro-ductility. Compared to aged SiCp/2024Al composite, the aged SiCp/7075Al composite showed an increase of about 200% in the tensile strain and 90% in the tensile strength, respectively. It is speculated that nano-η′ phases in the Al matrix significantly contributed to the strengthening effect while the interface layer between SiC and Al matrix might be beneficial to the strength and plasticity of SiCp/7075Al composite.