Molybdenum-Nitride Precipitation in Recrystallized and Cold-Rolled Fe-1 at. pct Mo Alloy

Recent Developments on Discontinuous Precipitation

“…Other behaviour was observed by Selg et al [59] in the recrystallized and cold rolled Fe-1at.% Mo-alloy at 853 K in a NH 3 /H 2 gas mixture. The nitride precipitation starts with the formation of submicroscopical Mo 2 N-type precipitates (no indication of α''-(Fe, Mo) 16 N 2 -type precursors was obtained) followed by a discontinuous transformation of the type:…”

Continuous and discontinuous precipitation in Fe-1 at.%Cr-1 at.%Mo alloy upon nitriding; crystal structure and composition of ternary nitrides

“…Mo is usually added to nitriding steels to enhance the properties of the unnitrided core of the components. However, Mo does also interact with N, albeit relatively slowly [7].…”

“…Upon nitriding of binary Fe-Cr [8]- [13] and Fe-Mo [7], [14] alloys initially cubic, NaCl-type CrN and cubic, NaCl-type γ-Mo 2 N (here 50 % of the octahedral-interstitial sublattice are not occupied by N), respectively, form as (semi-)coherent platelets with their broad faces parallel to the {100} α-Fe lattice planes and with a Baker-Nutting (BN) orientation relationship (OR) [15] with the ferrite matrix. The kinetics of formation of CrN is considerably faster than that of γ-Mo 2 N. This initial microstructure, composed of coherent nitrides finely dispersed in the ferrite matrix, is commonly referred to as continuously precipitated (CP).…”

“…The kinetics of formation of CrN is considerably faster than that of γ-Mo 2 N. This initial microstructure, composed of coherent nitrides finely dispersed in the ferrite matrix, is commonly referred to as continuously precipitated (CP). Upon nitriding for prolonged time, Fe-Cr alloys with sufficiently high Cr-content undergo a discontinuous coarsening (DC) reaction [8]- [13], whereas in Fe-Mo alloys a discontinuous precipitation (DP) reaction of γ-Mo 2 N to δ 3 -MoN occurs [7].…”

Thermodynamic Analysis of M₇C₃ Carbide Dissolution during Plasma Nitriding of an AISI D2 Tool Steel

“…[8][9][10][11] Both formation of nitrides and decomposition of carbides due to nitrogen absorption during plasma nitriding of alloyed steels have been reported. 1,[11][12][13][14][15][16][17] In particular, formation of iron nitrides, i.e., the compound layer, during plasma nitriding of diverse steels has been studied in depth. 11,12) Sun and Bell 1,9,11) pointed out that formation of compound layer should be inhibited in order to attain optimized coating-to-steel adherence.…”