Compressive deformation behavior of porous γ-TiAl with directional pores
Compressive deformation behavior of porous γ-TiAl with directional pores
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DOI：
10.1016/j.msea.2009.01.046
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发表时间：
2009-05
期刊：
影响因子：
6.4
通讯作者：
T. Ide;M. Tane;H. Nakajima
中科院分区：
文献类型：
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作者：
T. Ide;M. Tane;H. Nakajima
采用连续区熔技术，在加压氢/氦气氛下制备了具有单向排列的细长孔的莲花状多孔Ti52Al48。对不同孔隙率、加载方向与拉长孔方向平行和垂直的试件进行了压缩试验。莲花TiAl的压缩性能明显不同于具有延性基体的传统莲花金属。在气孔周围观察到变形和初始裂纹，并在气孔周围局部扩展。因此，试件不会发生致密化。这是由于脆性基质对局部大应力集中非常敏感。由此可见，荷花金属的压缩性能不仅与宏观孔结构有关，还与母材的延性程度有关。
Lotus-type porous Ti52Al48, possessing elongated pores aligned in one direction, was fabricated by a continuous zone melting technique under pressurized hydrogen/helium atmospheres. Compression tests were carried out on specimens with various porosities and with loading directions parallel and perpendicular to the elongated pore direction. The compressive properties of lotus TiAl significantly differ from those of conventional lotus metals with ductile matrix. Deformation and initial cracks are observed around the pores, and they progress around the pores locally. Therefore, the densification of the specimen does not occur. This is due to the brittle matrix, which is sensitive to local large stress concentration. Thus, it is concluded that compressive properties of lotus metals depend not only on macroscopic pore structure but also on the degree of ductility of matrix.