On the austenite stability of cryogenic Ni steels: microstructural effects: a review

Zhang, W. X.; Chen, Y. Z.; Cong, Y.B.; Liu, Y. H.; Liu, F.

doi:10.1007/s10853-021-06068-w

Cited by 30 publications

(7 citation statements)

References 127 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has been reported for a number of steels that fine austenite usually exhibits a lower M s temperature and enhanced thermal stability in comparison with coarse austenite [16,[26][27][28][29]. This effect is usually associated with an increased nonchemical driving force (i.e., elastic strain energy) for martensitic transformation due to structural refinement [25,26,[30][31][32]. Meanwhile, pre-straining obviously influenced the strength of the alloy.…”

Section: Discussionmentioning

confidence: 99%

Outstanding cryogenic strength-ductility properties of a cold-rolled medium-entropy TRIP Fe65(CoNi)25Cr9·5C0.5 alloy

Povolyaeva

Mironov

Shaysultanov

et al. 2022

Materials Science and Engineering: A

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Outstanding cryogenic strength-ductility properties of a cold-rolled medium-entropy TRIP Fe65(CoNi)25Cr9·5C0.5 alloy

Povolyaeva

Mironov

Shaysultanov

et al. 2022

Materials Science and Engineering: A

View full text Add to dashboard Cite

“…9Ni steel is an irreplaceable metal material in the liquefied natural gas sector due to its excellent thermomechanical properties and cryogenic toughness [4][5][6]. Ni-based cryogenic steels are commonly prepared through quenching and tempering (QT) treatments [7,8]. An appropriate heat treatment ensures excellent low-temperature toughness of 9Ni steel.…”

Section: Introductionmentioning

confidence: 99%

Effect of microstructural characteristics on the impact fracture behavior of cryogenic 9Ni steel

Zhang,

Li,

Zhao

et al. 2023

Mater. Res. Express

View full text Add to dashboard Cite

The percentage of shear fracture largely determines the service performance of 9Ni steel used in low-temperature pressure vessels. Through elemental analysis, microstructural characterization, and mechanical property tests, this study investigates why the percentage of shear fractures is low in 9Ni steel and clarifies the mechanism by which the microstructural characteristics influence the low-temperature impact behavior of 9Ni steel. It was found that cleavage fracture zones, formed when segregation bands appear in the microstructure, decrease the percentage of shear fractures at the impact fracture surface. Specifically, as the segregation area increases from 0.9% to 7.1%, the shear-fracture percentage in 9Ni steel sharply decreases from 100% to 65%, accompanied by a deterioration in low-temperature toughness. The segregation zone is enriched in austenite-forming elements (Ni, C, Mn), leading to a tempered martensite microstructure with a lath shape. The small number of high-angle grain boundaries and low interface bonding strength cannot effectively prevent crack initiation and propagation, resulting in brittle cleavage fracture. In contrast, the non-segregated zone is tempered sorbite with a uniform structure, several high-angle grain boundaries, and a high interface bonding strength. These features hinder crack initiation and propagation. Furthermore, the shear-fracture zone generated in the non-segregated zone exhibits ductile fracture characteristics.

show abstract

“…Metastable austenite tailoring is a long-standing hot topic in the field of steel materials [ 1 , 2 , 3 , 4 , 5 , 6 ]. By transformation-induced plasticity (TRIP) in metastable austenite, different kinds of advanced steels [ 7 , 8 , 9 ], including 3rd generation ultra-high strength automobile steel, high Co-Ni secondary hardening steels [ 10 , 11 ], cryogenic steels [ 12 , 13 ], etc., obtained excellent comprehensive mechanical properties. In order to provide precise guidance for metastable austenite tailoring, various researches paid much attention to the prediction of martensitic transformation from metastable austenite including both martensite start temperature and kinetics [ 14 ].…”

Section: Introductionmentioning

confidence: 99%

Prediction of Deformation-Induced Martensite Start Temperature by Convolutional Neural Network with Dual Mode Features

Wang

et al. 2022

Materials

View full text Add to dashboard Cite

Various models were established for deformation-induced martensite start temperature prediction over decades. However, most of them are empirical or considering limited factors. In this research, a dual mode database for medium Mn steels was established and a convolutional neural network model, which considered all composition, critical processing information and microstructure images as inputs, was built for Msσ prediction. By comprehensively considering composition, processing and microstructure factors, this model was more rational and much more accurate than traditional thermodynamic models. Also, by the full use of images information, this model has stronger ability to overcome overfitting compared with various traditional machine learning models. This framework provides inspiration for the similar data analysis issues with small sample datasets but different data modes in the field of materials science.

show abstract

On the austenite stability of cryogenic Ni steels: microstructural effects: a review

Cited by 30 publications

References 127 publications

Outstanding cryogenic strength-ductility properties of a cold-rolled medium-entropy TRIP Fe65(CoNi)25Cr9·5C0.5 alloy

Outstanding cryogenic strength-ductility properties of a cold-rolled medium-entropy TRIP Fe65(CoNi)25Cr9·5C0.5 alloy

Effect of microstructural characteristics on the impact fracture behavior of cryogenic 9Ni steel

Prediction of Deformation-Induced Martensite Start Temperature by Convolutional Neural Network with Dual Mode Features

Contact Info

Product

Resources

About