Effect of pore structure on mechanical properties of porous TiAl

Abstract

Based on two sets of TiAl powder, two kinds of porous TiAl were separately fabricated by powder metallurgical route including four stages. The porous TiAl with single pore structure (SPS) was prepared using pre-alloyed TiAl powder prior mechanical ball milling. Another porous TiAl with composite pore structure (CPS) was manufactured depending on composite mixture of Ti/Al elemental powders. The sintering was achieved at much lower temperature for the pre-alloyed power than for the elemental composite mixture. Compressive mechanical tests indicate that much higher mechanical strength can be obtained for SPS than for CPS at the same porosity. It was suggested that the difference of mechanical properties is ascribed to the variety of the compressive deformation process.

Microstructure Evolution and Pore Formation Mechanism of Porous TiAl3 Intermetallics via Reactive Sintering

“…10, the thickness of pore wall becomes thinner with the increase in the porosity and resulting in the gradual decline of mechanical properties [34,35]. Additionally, porous Ti-Al intermetallics are typical brittle materials and exist an inverse relationship between mechanical strength and porosity [36]. Ye et al [24] carried out the compressive test as a function of compacting pressure and concluded that the increase in pressure on green compact will result in the higher sintering density as well as the lower porosity, meanwhile, the compressive strength will be improved.…”

“…The combination of these properties make intermetallics suitable for industrial applications in automotive industry and energy generation [2][3][4]. In particular, Al-based intermetallic compounds attract much attention due to the outstanding properties of low density, high specific strength, excellent corrosion and oxidation resistance at high temperatures [5,6], including Ti-Al, Fe-Al, Nb-Al, Ni-Al and TiAl-Nb [7][8][9][10][11]. Recently, Ti-Al intermetallics have been fabricated into porous materials by vacuum sintering technique from elemental powders, and the durability is highly depend on its pore structures and pore-size distribution, which enable them good candidate for applications in filtration, solid-liquid separate and heat insulation [12][13][14].…”

Fabrication, Pore Structures and Mechanical Properties of (TiB2–Al2O3)/NiAl Porous Composites

“…Dong et al [6,7] have investigated the tensile strength and bending strength of porous NiAl and Ni 3 Al intermetallics. Nevertheless, there is rare report about compressive strength of porous NiAl intermetallics, which is equally important for engineering applications [22,32]. The compressive properties of porous TiAl with similar pore structure have been investigated [22,32].…”

Application of porous TiAl intermetallic compound in purification of industrial TiCl4 liquid in Ti metallurgy

“…At present, porous intermetallic compounds mainly consist of three types: (1) Ti based intermetallics, including TiAl [2,14,15], Ti 5 Si 3 [16,17], Ti 3 SiC 2 [13] and Ti 3 AlC 2 [18], (2) Fe based intermetallics, including FeAl [19] and FeAlCr [6] and (3) Ni based intermetallics, including Ni 3 Al [8] and Ni 3 Al-Mo [20]. Among them, porous Ti based intermetallics have good corrosion resistance to strong acid solution [1], porous Fe based intermetallics have good oxidation and sulfidation resistance at high temperature [6], and porous Ni based intermetallics have good electrochemical catalytic performance [7].…”