Warm ductility enhanced by austenite reversion in ultrafine-grained duplex steel

Cheng, Guan-Ju; Gault, Baptiste; Huang, Chin‐Cheng; Huang, Ching‐Yuan; Yen, Hung‐Wei

doi:10.1016/j.actamat.2018.01.060

Cited by 29 publications

(10 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5(a), owing to the balance between dislocation generation and annihilation as reported by Kocks. 17) Of course in few cases, DRX and austenite reversion have been observed in the ferrite as reported by Cheng et al 18) On the other hand, in the austenite, DRX is prominent owing to its lower SFE, which is activated by nucleation around γ /γ and γ /δ grain boundaries. After the critical strain is reached, DRX leads to the softening of flow stress and generates a peak stress as reported by Poliak and Jonas.…”

Section: Different Mechanical and Microstructural Mechanisms In The Austenite And Ferrite Of Duplex Stainless Steelmentioning

confidence: 82%

Flow Stress of Duplex Stainless Steel by Inverse Analysis with Dynamic Recovery and Recrystallization Model

et al. 2021

View full text Add to dashboard Cite

Section: Different Mechanical and Microstructural Mechanisms In The Austenite And Ferrite Of Duplex Stainless Steelmentioning

confidence: 82%

Flow Stress of Duplex Stainless Steel by Inverse Analysis with Dynamic Recovery and Recrystallization Model

et al. 2021

View full text Add to dashboard Cite

“…Hence, X-ray EDS mappings were conducted simultaneously. The detailed operation conditions were described in (Cheng et al, 2018). The nano-/microstructure was further investigated with FEI Tecnai G2 F20 200 kV TEM equipped with the X-Max 80 detector for X-ray EDS.…”

Section: Microstructural Characterizationsmentioning

confidence: 99%

Role of Vanadium Carbide in Hydrogen Embrittlement of Press-Hardened Steels: Strategy From 1500 to 2000 MPa

Lin

Chang

et al. 2021

Front. Mater.

Self Cite

View full text Add to dashboard Cite

This work investigated hydrogen trapping and hydrogen embrittlement (HE) in two press-hardened steels, 22MnB5 for 1,500 MPa grade and 34MnB5V for 2000 MPa grade, respectively. Superior to the 22MnB5 steel, the newly developed 34MnB5V steel has an ultimate tensile strength of over 2000 MPa without sacrificing ductility due to the formation of vanadium carbides (VCs). Simulated press hardening was applied to two steels, and hydrogen was induced by cathodic charging. Susceptibility to HE was validated by slow strain-rate tensile test. When hydrogen content was high, the 34MnB5V steel fractured in elastic regime. However, when hydrogen content was 0.8–1.0 ppmw, the 34MnB5V steel bore much higher stress than the 22MnB5 steel before fracture. The behavior of hydrogen trapping was investigated by thermal desorption analyses. Although the two steels trapped similar amounts of hydrogen after cathodic charging, their trapping mechanisms and effective trapping sites were different. In summary, a finer prior austenite grain size due to the pinning effect of VCs can also improve the toughness of 34MnB5V steel. Moreover, trapping hydrogen by grain boundary suppresses the occurrence of hydrogen-enhanced local plasticity. Microstructural refinement enhanced by VCs improves the resistance to HE in 34MnB5V steel. Importantly, the correlation between hydrogen trapping by VCs and improvement of HE is not significant. Hence, this work presents the challenge in designing irreversible trapping sites in future press-hardened steels.

show abstract

“…However, due to the difference in the composition between various IF steels, the microstructure, texture, and properties would be different-even in the same process. In addition, it was also reported that the texture developed during hot rolling was found to be inhomogeneous, influenced by the main texture components of the parent austenite [16]. In addition, the texture of the IF steel, which was evolved during cold rolling, was investigated too [17,18].…”

Section: Introductionmentioning

confidence: 99%

Development of Ultrafine Grain IF Steel via Differential Speed Rolling Technique

Hamad

2021

Metals

View full text Add to dashboard Cite

The aim of this paper was to investigate the microstructural development and properties of interstitial free (IF) steel fabricated using the DSR (differential speed rolling) process. Severe plastic deformation of the DSR passes was imposed on the sample for up to four passes, leading to ~1.7 total strain with a speed ratio of 1:4 between the two rolls. Microstructural observation revealed that the equiaxed grain size of ~0.7 µm, including the formation of grain boundaries with a high angle of misorientation, was reached after four operations of DSR, which was attributed to the grain subdivision of severely elongated ferrite grain. Since the deformation mode of the DSR operation was dominated by severe shear deformation, the main shear texture of the bcc components appeared in all DSR operations in which the α-fiber of the {110} slip became a main component in accommodating the severe plastic deformation of the DSR process. The intensity of the shear texture, the {110} and {112} slip, increased by increasing the number of passes. Moreover, the γ-fiber of the <112>-type planes was activated as a result of the alternation of the shear direction during sample rotation. The microhardness and room temperature tensile tests revealed that the strength of the IF steel improved as the amount of strain increased, and this was attributed to the grain refinement and texture characteristics of the samples after the DSR processing.

show abstract

Warm ductility enhanced by austenite reversion in ultrafine-grained duplex steel

Cited by 29 publications

References 56 publications

Flow Stress of Duplex Stainless Steel by Inverse Analysis with Dynamic Recovery and Recrystallization Model

Flow Stress of Duplex Stainless Steel by Inverse Analysis with Dynamic Recovery and Recrystallization Model

Role of Vanadium Carbide in Hydrogen Embrittlement of Press-Hardened Steels: Strategy From 1500 to 2000 MPa

Development of Ultrafine Grain IF Steel via Differential Speed Rolling Technique

Contact Info

Product

Resources

About