Atom-Probe Tomographic Investigation of Austenite Stability and Carbide Precipitation in a TRIP-Assisted 10 Wt Pct Ni Steel and Its Weld Heat-Affected Zones

Jain, Divya; Seidman, David N.; Barrick, Erin J.; DuPont, J. N.

doi:10.1007/s11661-018-4470-1

Cited by 8 publications

(7 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The presence of fine austenite grains in the ASB in a similar alloy was reported previously and confirmed using microdiffraction[44]. In their TEM-EDS analysis of an ASB, the partitioning behavior of the substitutional elements, Ni and Mn, to the austenite-phase are unclear when compared with the P a g e | 4811…”

supporting

confidence: 76%

“…Low-carbon concentration (<0.1 wt% C) in steel is suitable for Naval structural applications for good weldability [5,6] and a Nirich austenite-phase formation in a tempered martensitic matrix increases ductility and toughness in steels [7,8]. Specific heat treatments, such as the quenching-lamellarizing-tempering (QLT) procedure [9][10][11][12] enhance the strength and toughness of 10 wt.% Ni steels for use at cryogenic temperatures by stabilizing the austenite-phase (up to ~20 vol.%) in a tempered martensitic matrix.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Temperature Increases and Thermoplastic Microstructural Evolution in Adiabatic Shear-Bands in a High-Strength and High-Toughness 10 wt.% Ni Steel

Baik¹,

Gupta

Kumar

et al. 2020

SSRN Journal

Self Cite

View full text Add to dashboard Cite

A 10 wt.% nickel-steel has been developed for high pressures and low-temperature applications, due to its high strength, excellent toughness, and low ductile-to-brittle transition temperature (DBTT). Under dynamic loading conditions this steel is, however, prone to shear localization that manifests as adiabatic shear bands (ASBs). The temperature increases and thermoplastic microstructural evolution in the ASB are studied in detail, from the macroscopic length scale to the atomic-scale employing correlative electron-backscatter diffraction (EBSD), transmission electron microscopy (TEM), and atom-probe tomography (APT). From a calculation of the temperature increase under adiabatic conditions, based on the conversion of plastic-work to heat generation, the microstructural transitions in the ASB are discussed specifically for: (i) a b.c.c.-f.c.c. phase-transformation and their elemental partitioning; (ii) the thermodynamic model for the compositional change of the V(Nb)-rich carbonitride precipitates during a temperature increase; and (iii) grain-refinement and rotation by dynamic/mechanical recrystallization processes. Solute segregation at subgrain boundaries, measured using the Gibbsian interfacial excess methodology, reveals how solute segregation contributes to the instability of localized shear-deformation by promoting the depinning of solute elements and the migration of a grain boundary. Finally, a kinetic model for grain refinement/rotation within an ASB is described by the dynamic recrystallization behavior with: (i) subgrain formation; (ii) rotation/refinement by P a g e | 48 2 deformation; and (iii) grain growth by subgrain coalescence with further rotation and a temperature increase. The temperature increase under dynamic deformation in an ASB promotes grain boundary migration and subgrain coalescence to create a large degree of equiaxed grains with a low density of imperfections.

show abstract

supporting

confidence: 76%

Section: Introductionmentioning

confidence: 99%

Temperature Increases and Thermoplastic Microstructural Evolution in Adiabatic Shear-Bands in a High-Strength and High-Toughness 10 wt.% Ni Steel

Baik¹,

Gupta

Kumar

et al. 2020

SSRN Journal

Self Cite

View full text Add to dashboard Cite

show abstract

“…Cu atoms tend to agglomerate in the supersaturated matrix and form high-density metastable Cu-rich atomic clusters. When the tempering temperature is 560 °C, the Cu-rich phase and carbides are coarsened, and the size of the Cu-rich phase increases, and the number of Cu-rich phases decreases [ 22 ]. As shown in Figure 11 , when the tempering temperature is 560 °C, NiMn tends to be clustered at edge of the Cu-rich phase.…”

Section: Resultsmentioning

confidence: 99%

Effect of Temperature on Microstructure and Mechanical Properties of Fe-9Ni-2Cu Steel during the Tempering Process

Huang

Wang

et al. 2021

Materials

View full text Add to dashboard Cite

In this paper, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray stress meter (XRSA), atom probe tomography (APT), hardness, and tensile tests were used to study the effect of tempering temperature on the microstructure and properties of Fe-9Ni-2Cu steel. The results show that after the quenched samples were tempered at 460 °C for 2 h, the hardness values increased from 373 to 397 HV, and elongation also increased from 13% to 16%. With the tempering temperature increasing from 460 to 660 °C, the hardness firstly decreases from 397 to 353 HV and then increases to 377 HV, while the elongation increases to 17% and then decreases to 11%. The variation of the mechanical properties greatly depends on the evolution of the Cu-rich phase and carbides. The precipitation strengthening of the Cu-rich phase and carbides leads to the increase of hardness, but when the precipitate is coarsened, the precipitation strengthening weakens, and then, the hardness increases. When the tempering temperature is 560 °C, a large amount of stable reverse transformation austenite was formed with a content of 7.1%, while the tensile strength reached the lowest value of 1022 MPa and the elongation reached the maximum value of 17%.

show abstract

“…All samples for heat treatment were cut from a plate that was hot rolled to a thickness of 25 mm and air-cooled to room temperature. A three-stage QLT heat treatment identified in the literature for this steel [37][38][39][40][41][42][43][44] was performed and included: (i) An austenitizing step at 800°C for 1 hour followed by water quenching (the Q step in QLT) (ii) Tempering at 650°C for 40 min followed by water quenching to room temperature (the L step in QLT) (iii) A second tempering at 590°C for 1 hour followed by a final water quench (the T step in QLT).…”

Section: Methodsmentioning

confidence: 99%

“…[18,29,30,32] One such steel that has drawn recent attention is an Fe-10Ni-1.0Mo-0.6Mn-0.6Cr-0.08V-0.1C (wt pct) steel (hereafter referred to as the ''10Ni steel'' for brevity) that has been variously heat-treated including a twostage temper called the quench-lamellerize-temper (QLT) treatment. [36][37][38][39][40][41][42][43][44] In this QLT condition, this steel has been shown to have high quasi-static strength and toughness as well as superior ballistic resistance. [37] The QLT treatment on the 10Ni steel produces a dispersion of fine, Ni-rich, thermally stable austenite precipitates in a ferritic matrix [37,40] ; it is thought that the high quasi-static toughness and the resistance to shear localization during dynamic deformation are related to the mechanical instability of this precipitated austenite.…”

Section: Introductionmentioning

confidence: 99%

Microstructural Evolution in an Fe-10Ni-0.1C Steel During Heat Treatment and High Strain-Rate Deformation

Harding

Mouton

Gault

et al. 2020

Metall Mater Trans A

View full text Add to dashboard Cite

1C (wt pct) steel in a multi-step heat-treated condition called 'QLT' is understood by tracking its evolution in each step using transmission electron microscopy (TEM) and atom probe tomography; further, the consequence of high strain-rate deformation on the site-specific change in the QLT microstructure is examined by microdiffraction and energy dispersive spectroscopy in the TEM. The QLT treatment results in two generations of austenite (arising from the Land the T-step) with differing Ni content. The primary focus of this study is on the thermal and mechanical stability of the precipitated austenite and the influence of austenite chemistry and size on the stability. Kolsky bar compression experiments were conducted to isolate a situation where an adiabatic shear band propagated partway through the specimen. Examination of the microstructure in such a specimen showed both generations of austenite to be present far from the shear band, ahead of the shear band and adjacent to the shear band. The austenite immediately ahead of the shear band was fragmented. Within the shear band, evidence was found for deformation-induced transformation to martensite. These findings are discussed within the context of improved damage tolerance and ballistic resistance observed earlier in field tests.

show abstract

Atom-Probe Tomographic Investigation of Austenite Stability and Carbide Precipitation in a TRIP-Assisted 10 Wt Pct Ni Steel and Its Weld Heat-Affected Zones

Cited by 8 publications

References 69 publications

Temperature Increases and Thermoplastic Microstructural Evolution in Adiabatic Shear-Bands in a High-Strength and High-Toughness 10 wt.% Ni Steel

Temperature Increases and Thermoplastic Microstructural Evolution in Adiabatic Shear-Bands in a High-Strength and High-Toughness 10 wt.% Ni Steel

Effect of Temperature on Microstructure and Mechanical Properties of Fe-9Ni-2Cu Steel during the Tempering Process

Microstructural Evolution in an Fe-10Ni-0.1C Steel During Heat Treatment and High Strain-Rate Deformation

Contact Info

Product

Resources

About