Microstructural and mechanical characterization of Nb-based in situ composites from Nb–Si–Ti ternary system

Effect of Gallium on microstructure and mechanical properties of Nb–Si eutectic alloy

“…K i ¼ 0:0123$ðEÞ 0:4 ðHÞ 0:1 ðP=1Þ 0:5 (2) here 'E' is the Young's modulus, 'H' is the hardness, 'P' is load and 'l' is the length of crack from the corners of Vickers indentation. Fig.…”

“…Hence, successful implementation of these materials needs improvement in their toughness both at room temperature as well as at elevated temperatures. Among all the Nb, V and Cr based intermetallics, the ones belonging to NbeSi system have shown greater promise because of there prospective future applications in gas turbine and aircraft engines as a replacement of current Ni based super alloys [1,2]. Nb rich NbeSi alloys have low density (6.6e7.2 gm/cm 3 ) and high temperature oxidation resistance [3,4].…”

The 773 K isothermal section of the ternary phase diagram of the Nb–Ti–Si system

“…Binary titanium silicides were not detected in the case of 20 at.% Ti addition to the Nb-Si system. Most of the Ti atoms dissolve into the niobium silicides, causing the formation of (Nb,Ti) 5 Si 3 solid solutions [18]. The binary systems of Ti-Si, Nb-Si are somewhat similar to one another for each of them forms the M 5 Si 3 -type compound (Ti 5 Si 3 , Nb 5 Si 3 ).…”

Thermodynamic assessment of the Nb–Si–Ti system

“…To achieve such a property balance, the elements such as Ti, Hf, Cr, and Al are added to the composites and the significant progress has been made in improving the properties of the materials [7][8][9][10]. The Ti addition can stabilize the Nb 3 Si phase to lower temperatures, reduce the melting point of the composites, and play a key role in controlling the fracture toughness, the strength and the ductility of the solid solution [7,[10][11][12][13][14]. For the purpose of the advanced design of the Nb-Si based composites, a good understanding of the phase equilibria and thermodynamic properties of the multi-component alloys, such as the Nb-Si-Ti-Al-Cr-Hf system, is extremely necessary.…”