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

Steiner, Tobias; Meka, Sai Ramudu; Rheingans, Bastian; Bischoff, E.; Waldenmaier, T.; Yeli, Guma; Martin, T.; Bagot, P.A.J.; Moody, Michael P.; Mittemeijer, E. J.

doi:10.1080/14786435.2016.1167282

Cited by 19 publications

(14 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The in‐diffusion of nitrogen can result in preferential reaction with alloying elements such as Cr, Mo, and Mn where the nitrogen content is below 1 wt.%, which could be a reason for the increased hardness through the tube. The presence of for example Mo nitrides was not revealed with SEM, however, such precipitates have been observed to be submicron level at 580°C . At the low temperatures in this study, Mo is virtually immobile, so even if Mo nitrides were formed, they would remain as fine nitrides.…”

Section: Discussioncontrasting

confidence: 59%

“…After nitriding of carbon steels, hardness values of 30–35 HRC (equivalent to 300–340 HV) were measured which is just below the region observed for the grate . The incorporation of fine MoN/MoN 2 led to an increase in hardness of up to 100 HV for a steel with 1 at.% Mo (1.68 wt.%) . In addition, the ferrite peaks from XRD became broader and shifted to lower 2θ levels due to the presence of fine Mo nitrides precipitates .…”

Section: Discussionmentioning

confidence: 93%

See 1 more Smart Citation

Nitridation of grate in a biomass‐fired boiler

Montgomery

Dahl

Grumsen

et al. 2019

Materials & Corrosion

View full text Add to dashboard Cite

After a straw‐fired power plant in Denmark had been in operation for 16 years with 93,815 hr operation, there was a need for overlay welding repair of the grate due to a decrease in wall thickness from erosion/corrosion. The grate consisted of 15Mo3 (Werkstoff nr. 1.5415) tubes where water/steam flows through, which were welded together with fins, and where one side faced the combustion zone coming into contact with the fuel (the side that required weld overlay). The water/steam temperature was 320°C and the surface metal temperature was estimated to be 350°C. However, there were difficulties when trying to overlay weld the grate as the weld pool was unstable. The microhardness measurements on cross‐sections of the tubes revealed a higher hardness of the tube facing the combustion zone compared to opposite the combustion zone. In addition, there was higher hardness adjacent to the combustion side than the steam/water side. Analysis of etched cross‐sections with light optical and scanning electron microscopy revealed the presence of acicular structures at the convex surface. Further analysis has been conducted with X‐ray diffraction and a LECO nitrogen analyser indicating the presence of iron nitrides. Reasons for their evolution and implications for the repair welding are discussed.

show abstract

Section: Discussioncontrasting

confidence: 59%

Section: Discussionmentioning

confidence: 93%

Nitridation of grate in a biomass‐fired boiler

Montgomery

Dahl

Grumsen

et al. 2019

Materials & Corrosion

View full text Add to dashboard Cite

show abstract

“…As a result, a lamellar microstructure develops, which is composed of alternate lamellae of precipitate and matrix with an incoherent interface [16,21,27]. Next to (ongoing) continuous coarsening, such discontinuous coarsening has been observed in a number of nitrided iron-based alloys: Fe-Cr [27][28][29][30], Fe-V [31], Fe-Mo [32], and Fe-Cr-Mo 1 [33].…”

Section: Introductionmentioning

confidence: 95%

Diffraction-line shifts and broadenings in continuously and discontinuously coarsening precipitate-matrix systems: coarsening of initially coherent nitride precipitates in a ferrite matrix

et al. 2015

View full text Add to dashboard Cite

The initial precipitation of misfitting particles can be accompanied by elastic accommodation of the precipitate/matrix misfit leading to considerable matrix lattice dilatation/contraction and variable lattice microstrain. In this stage, the entire assembly of matrix and precipitate particles, as a whole, can diffract coherently. Upon aging of the system, relaxation of the accommodated misfit can occur by continuous and/or discontinuous coarsening of the precipitates. These processes are associated with distinctly different, characteristic diffraction phenomena, also involving a transition from coherent to incoherent diffraction of precipitates and matrix. For the case of, initially fully coherent, alloying element nitrides in a homogeneously nitrided ferrite matrix, these effects have been identified and analyzed, thus allowing tracing of misfitrelaxation processes.

show abstract

“…Currently, the Cameca (Gennevilliers, France) LEAP series is by far the most widely used atom probe instrument, with over 85 installed worldwide by early 2016. These instruments are used by many research institutions to study applications including identifying the chemistry of small phase changes in metals (Steiner et al, 2016), characterizing the boundaries of corrosion surfaces (Pedrazzini et al, 2016) and even individual cracks (Meisnar et al, 2015), whole semiconductor transistors (Inoue et al, 2009), catalysis (Li et al, 2012), and more recently moving outside of traditional materials science applications and into fields such as geoscience (Valley et al, 2014) and biological materials (Gordon et al, 2012).…”

Section: Introductionmentioning

confidence: 99%

Comparing the Consistency of Atom Probe Tomography Measurements of Small-Scale Segregation and Clustering Between the LEAP 3000 and LEAP 5000 Instruments

et al. 2017

Self Cite

View full text Add to dashboard Cite

The local electrode atom probe (LEAP) has become the primary instrument used for atom probe tomography measurements. Recent advances in detector and laser design, together with updated hit detection algorithms, have been incorporated into the latest LEAP 5000 instrument, but the implications of these changes on measurements, particularly the size and chemistry of small clusters and elemental segregations, have not been explored. In this study, we compare data sets from a variety of materials with small-scale chemical heterogeneity using both a LEAP 3000 instrument with 37% detector efficiency and a 532-nm green laser and a new LEAP 5000 instrument with a manufacturer estimated increase to 52% detector efficiency, and a 355-nm ultraviolet laser. In general, it was found that the number of atoms within small clusters or surface segregation increased in the LEAP 5000, as would be expected by the reported increase in detector efficiency from the LEAP 3000 architecture, but subtle differences in chemistry were observed which are attributed to changes in the way multiple hit detection is calculated using the LEAP 5000.

show abstract

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

Cited by 19 publications

References 70 publications

Nitridation of grate in a biomass‐fired boiler

Nitridation of grate in a biomass‐fired boiler

Diffraction-line shifts and broadenings in continuously and discontinuously coarsening precipitate-matrix systems: coarsening of initially coherent nitride precipitates in a ferrite matrix

Comparing the Consistency of Atom Probe Tomography Measurements of Small-Scale Segregation and Clustering Between the LEAP 3000 and LEAP 5000 Instruments

Contact Info

Product

Resources

About