Boron-doped molybdenum silicides for structural applications

FeAl and Mo–Si–B intermetallic coatings prepared by thermal spraying

“…High-temperature intermetallic compounds are being studied and developed for applications in advanced power plants (coal-fired plants, land-based and aero engine gas turbines) due to their potential high-temperature strength, oxidation resistance, and lowered density relative to conventional Fe-and Ni-based alloys [1][2][3]. These materials continue to face a number of challenges, however, particularly with regard to obtaining a combination of high-temperature creep strength and low-temperature ductility.…”

Defects Interaction on the Mechanical Properties during Transition Formation of (Mo, Cr)<SUB>3</SUB>Si Intermetallic Alloys

“…Fleischer et al [10] studied the mechanical properties of similar intermetallic compounds. They reported the microhardness value of 1200 HVN at room temperature for Cr 3 Si, which was lower than the value reported for Mo 3 Si [9]. The analysis of the transition of Mo 3 Si to Cr 3 Si may provide important information about the optimal concentration of Cr to improve the ductility of the Mo 3 Si considering the thermal defects affectation.…”

“…Shah et al [6] investigated the intermetallics Nb 3 Al and Cr 3 Si, evaluated their mechanical properties at room and high temperature and reported that Cr 3 Si presented an excellent behavior at high temperature, but with limited possibilities of being alloyed. Raj [7] [8] evaluated the mechanical properties of Cr 3 Si and Cr-Cr 3 Si produced by arc cast and powder metallurgy, where the room temperature fracture toughness was determined in the range of 2.0 and 3.0 MPa m 1/2 , which was comparable with the value reported for Mo 3 Si [9]. Fleischer et al [10] studied the mechanical properties of similar intermetallic compounds.…”

Fracture and fatigue resistance of Mo–Si–B alloys for ultrahigh-temperature structural applications

“…In previous reports [8,9], we have described alloys containing (α-) molybdenum particles surrounded by the hard but brittle Mo 3 Si and Mo 5 SiB 2 (T2) intermetallic phases, which display definitive, but still small, improvements in toughness relative to monolithic silicides. Clearly, the key to achieving high fracture resistance in these materials is in making more effective use of the relatively ductile molybdenum phase, not unlike nickel-base (γ/γ′) superalloys, where high fracture toughnesses are obtained with a similarly high fraction of intermetallic (γ′) precipitates.…”

“…In this regard, molybdenum silicides and borosilicides have shown promise in improving the oxidation and creep resistance [2][3][4], leading to the development of two specific MoSi-B alloy systems by Akinc et al [2][3][4][5] and Berczik et al [6,7]; however, the silicide compounds alone are quite brittle and provide little fracture resistance for most structural applications without significant additional toughening. In previous reports [8,9], we have described alloys containing (α-) molybdenum particles surrounded by the hard but brittle Mo 3 Si and Mo 5 SiB 2 (T2) intermetallic phases, which display definitive, but still small, improvements in toughness relative to monolithic silicides.…”