冷冻浇注制备多孔钛铝基金属间化合物的显微组织及性能（英文）

Microstructures and properties of porous TiAl-based intermetallics prepared by freeze-casting

通过冷冻浇注法制备具有定向长孔结构的多孔钛铝基金属间化合物。采用Ti-43Al-9V-1Y工程级粉末(D50=50μm)、羧甲基纤维素以及瓜尔豆胶配制水基浆料用于冷冻浇注。研究结果表明,在-5℃的冷冻条件下可制备具有定向长孔结构的多孔钛铝,并且可通过改变浆料中粉末的体积分数来控制孔隙结构。当粉末含量从10%增加至30%(体积分数)时,总孔隙率由81%减小至62%,定向孔宽度由约500μm减小至约270μm。随着孔隙率的降低,沿定向孔方向的压缩强度由16MPa增加至120MPa。另外,所制备的多孔钛铝的等效热导率较低,最高为1.81 W/(m·K),并且受孔方向的影响呈现出各向异性。

Preparation of porous Ti Al-based intermetallics with aligned and elongated pores by freeze-casting was investigated. Engineering Ti-43 Al-9V-1Y powder(D50=50 μm), carboxymethyl cellulose, and guar gum were used to prepare the aqueous-based slurries for freeze-casting. Results showed that the porous Ti Al was obtained by using a freezing temperature of -5 ℃ and the pore structure was tailored by varying the particle content of slurry. The total porosity reduced from 81% to 62% and the aligned pore width dropped from approximately 500 to around 270 μm, with increasing the particle content from 10 to 30 vol.%. Furthermore, the compressive strength along the aligned pores increased from 16 to 120 MPa with the reduction of porosity. The effective thermal conductivities of porous Ti Al were lower than 1.81 W/(m·K) and showed anisotropic property with respect to the pore orientation.