Effects of pre-annealing conditions on the microstructure and properties of vanadium-bearing dual-phase steels produced using continuous galvanizing line simulations

Gong, Yu; Uusitalo, Juha; Meng, Hua; Wu, Yingjie; DeArdo, A. J.

doi:10.1007/s10853-019-03338-6

Cited by 12 publications

(18 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, this and other recent studies [3] [4] have shown secondary pre-annealing effects such as hot band coiling temperature and cold reduction can also greatly influence the amount of austenite formed during the anneal. Therefore, a good combination of coiling temperature and cold reduction can help ensure that a large amount of austenite can be obtained during intercritical annealing in the short time available [5]. It has been found that the stored energy of the cold band is a good indicator to evaluate the ability to form large amounts of austenite during the anneal.…”

Section: List Of Tablesmentioning

confidence: 99%

“…Taking the logarithm of both sides of Equation (2-10), work hardening exponent n can be obtained by Equation (2)(3)(4)(5)(6)(7)(8)(9)(10)(11). This model is Hollomon model.…”

Section: Work Hardening Behaviormentioning

confidence: 99%

“…The modified Crussard-Jaoul (C-J) analysis of work hardening behavior was expressed in Equation (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14).…”

Section: Work Hardening Behaviormentioning

confidence: 99%

“…is independent on grain sizes and it is the flow stress of the grain interior [55]; while k(ε)D −1/2 depends on grain sizes, and it is the strength attributed to the resistance of the movement of dislocation near the grain boundaries. Equation (2-17) can be expressed by Equation (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18).…”

Section: Grain-size Strengtheningmentioning

confidence: 99%

“…where, M is Taylor factor, α is a number, G is shear modulus, b is Burgers vector, S V is grain boundary area per volume and θ is misorientation angle. At high strain, the low angle grain boundaries (LAGBs) transform into high angle grain boundaries (HAGBs) [56], so the Equation (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18) can be rewritten by Equation (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19).…”

Section: Grain-size Strengtheningmentioning

confidence: 99%

See 4 more Smart Citations

Processing, Microstructures and Properties of Ultra-High Strength, Low Carbon and V-Bearing Dual-Phase Steels Produced on Continuous Galvanizing Lines

Wu¹,

DeArdo²

2018

Contributed Papers From MS&T17

Self Cite

View full text Add to dashboard Cite

One of the most popular elements in weight reduction programs in the automotive industry is high strength zinc coated dual-phase steel produced on continuous hot dipped galvanizing lines. The high strength is needed for mass reduction, while the protective zinc coating is needed to prevent corrosion of the thin gage cold rolled steel. The present study was aimed to explore an optimized way to produce such dual-phase steels with ultra-high tensile strength (UTS > 1280MPa), good global ductility (TE > 18%), excellent local ductility (sheared-edge ductility, HER > 40%) and products of UTS × TE > 22000 MPa × %, conforming to data of AHSS Generation III steel. A steel of this kind is referred to as a third-generation advanced high strength steel. By altering chemical compositions (0.15wt.% carbon), pre-annealing conditions (different hot band coiling temperatures and cold reductions), annealing conditions (different intercritical annealing temperatures) and annealing paths (standard galvanizing or supercool processing), this study set out to investigate the effects of these factors on the microstructures and mechanical properties of dual-phase steels. Results showed that the stored energy of cold rolled steel with 0.15wt.% carbon was much higher than that of carbon containing 0.1wt.% carbon, generating numerous lattice defects during deformation and providing more driving force for formation of austenite and v recrystallization of ferrite during the intercritical anneal. In addition, it was found that the volume fraction of martensite increased with the combination of low coiling temperature, high cold reduction, and high annealing temperature, thereby increasing the tensile strength. Furthermore, the microstructural analysis and tensile testing results and showed that the tensile strength of dual-phase steel with 0.15Wt.% carbon, combined with the ultrafine microstructures (average ferrite grain sizes reached 1-2µm) could approach 1300MPa without loss of ductility and with hole expansion ratios, in some cases, reaching 35%. Since the relative hardness of the hard martensite and soft ferrite is important in controlling sheared-edge ductility, the nanohardness results of these phases were measured. It was revealed that the martensite hardness decreased with increasing volume fraction, at a given carbon content, indicating the tensile strength was independent of the martensite hardness. Other mechanical properties, such as yield strength, YS/UTS ratio, hardness and work hardening behavior, of dual-phase steels controlled by the factors mentioned above were correlated to the microstructural features. The hypothesis that the bulk carbon content would be a major factor in controlling the strength of these steels was vindicated by the results of this study.

show abstract

Section: List Of Tablesmentioning

confidence: 99%

“…Taking the logarithm of both sides of Equation (2-10), work hardening exponent n can be obtained by Equation (2)(3)(4)(5)(6)(7)(8)(9)(10)(11). This model is Hollomon model.…”

Section: Work Hardening Behaviormentioning

confidence: 99%

“…The modified Crussard-Jaoul (C-J) analysis of work hardening behavior was expressed in Equation (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14).…”

Section: Work Hardening Behaviormentioning

confidence: 99%

Section: Grain-size Strengtheningmentioning

confidence: 99%

Section: Grain-size Strengtheningmentioning

confidence: 99%

See 3 more Smart Citations

Processing, Microstructures and Properties of Ultra-High Strength, Low Carbon and V-Bearing Dual-Phase Steels Produced on Continuous Galvanizing Lines

Wu¹,

DeArdo²

2018

Contributed Papers From MS&T17

Self Cite

View full text Add to dashboard Cite

show abstract

Effect of Preannealing on Microstructural Evolution and Tensile Properties of a Novel Nickel‐Based Superalloy

Jia

et al. 2020

Adv Eng Mater

View full text Add to dashboard Cite

Nickel-based superalloys are widely applied in aeronautical, aerospace, nuclear, and petrochemical industries, due to their excellent high-temperature mechanical properties. [1-3] Disc superalloys, such as Allvac 718Plus, [4] Waspaloy, [5] FGH100L, [6] and GH4065, [7,8] are the typical representatives of nickel-based superalloys for the critical rotating components of aircraft engines and gas turbines. The nickel-based alloy GH4065 developed for aerospace turbine disc superalloys is strengthened by gamma prime (γ 0) precipitates (L1 2 structure, Ni 3 (Al, Ti)). Also, GH4065 was designed as a novel disc superalloy for service temperature up to 750 C. For turbine discs, it is usually formed by hot die forging. The microstructure of GH4065 alloy after forging is generally not uniform due to inhomogeneous plastic deformation, which is inevitable and cannot be ignored in the forging process. [9] Generally, the properties of components largely rely on their microstructure, and a homogeneous microstructure is essential to achieve better performance. Consequently, it is necessary to pay attention to the relationship among processing variables, microstructure, and properties for disc superalloys. Heat treatment plays a significant role in controlling the microstructure and properties for disc superalloys. Traditionally, heat treatment combined with solution treatment and aging treatment is adopted to adjust the microstructure and performance of nickel-based superalloys. For the conventional heat treatment, previous studies reported the influence of heat treatment on microstructural evolution or mechanical properties of nickel-based superalloys. [9-20] Jackson and Reed [10] pointed out that the heat treatment of 24 h at 700 C is the optimal condition for the creep properties of a disc superalloy, Udimet 720Li. In these studies, particular attention is only paid to the characterization of γ 0 particle size distributions. Chang et al. [16] showed that the direct aging heat treatment is the best one for the hot-isostatic-pressed Inconel 718 powder compact, due to the balance of strength and ductility. However, its yield strength (YS) is lower than that of the one that is solution treated because of the aging of precipitates. Chen et al. [9] proposed the optimum annealing parameters are 980 C for 10 min, which lead to the occurrence of static recrystallization (SRX) and improve the homogeneous nature of GH4169 alloy. However, the effect of preannealing (PA) prior to solution treatment on the evolution of strengthened phase, mechanical properties, and deformation mechanism is not discussed in the aforementioned studies. Moreover, the effect of PA on both microstructural evolution and tensile properties in disc superalloys has been barely reported till now. The PA in other alloys was studied, such as dual-phase steels, [21] stainless steel fiber felt, [22] and corrosion-resistant superalloy.

show abstract

Influence of processing factors on the sheared-edge formability of vanadium bearing dual-phase steels produced using continuous galvanizing line simulations

Gong

Meng

et al. 2020

J Mater Sci

View full text Add to dashboard Cite

Effects of pre-annealing conditions on the microstructure and properties of vanadium-bearing dual-phase steels produced using continuous galvanizing line simulations

Cited by 12 publications

References 27 publications

Processing, Microstructures and Properties of Ultra-High Strength, Low Carbon and V-Bearing Dual-Phase Steels Produced on Continuous Galvanizing Lines

Processing, Microstructures and Properties of Ultra-High Strength, Low Carbon and V-Bearing Dual-Phase Steels Produced on Continuous Galvanizing Lines

Effect of Preannealing on Microstructural Evolution and Tensile Properties of a Novel Nickel‐Based Superalloy

Influence of processing factors on the sheared-edge formability of vanadium bearing dual-phase steels produced using continuous galvanizing line simulations

Contact Info

Product

Resources

About