Untitled

Aerosol nanoparticles in the Fe1−xCrx system: Room-temperature stabilization of the σ phase and σ→α-phase transformation

“…In the past, metastable -FeCr phase has been detected at room temperature in sputtered thin films [13][14][15] and in alloys with additions of a third element ͑e.g., Ti, Al, and Sn͒ [16][17][18][19] or after subjecting ␣-FeCr to long thermal treatments. [20][21][22] However, as previously shown by Petrov and co-workers, 23,24 nanoparticles of hightemperature phases of metals and alloys can be stabilized at room temperature by gas evaporation. Figure 3 presents the dependencies of the -phase content and the ␣-FeCr lattice parameter on the sample composition, as obtained from Rietveld refinements of the diffraction data.…”

Microstructural evolution during aging of novel superferritic stainless steel produced by the HIP process

“…1,[3][4][5] The intermetallic phases forming also have a higher Cr and Mo content than the matrix; 6 sigma phase in particular is a hard, brittle phase based on the formula FeCr, adopting a tetragonal crystal structure and taking other elements such as molybdenum into substitutional solid solution. 3,5,7,8 Consequently, the brittle nature of sigma and chi phases could cause embrittlement in superferritic stainless steels. 3 The time-temperature-precipitation curve varies in superferritic stainless steels depending on composition.…”