Microstructural Control and Alloy Design for Improving the Resistance to Delayed Fracture of Ultrahigh-Strength Automotive Steel Sheets

Senuma, Takehide; Okayasu, Mitsuhiro; Mohrbacher, Hardy

doi:10.3390/met13081368

Cited by 2 publications

(2 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Developments in the automobile industry have caused serious problems in terms of energy consumption and environmental pollution, so the need for lightweight components is becoming more important. It has been reported [1] that using high-strength leaf springs is an effective way to achieve weight reductions in the automobile industry. At the same time, considering the harsh service environment and complex force situations of springs, it is necessary to pursue super-high strength materials that also have good mechanical properties and high impact toughness, so that vehicles can better absorb and disperse vibrations and impacts on the road during driving.…”

Section: Introductionmentioning

confidence: 99%

Heat Treatment Process, Microstructure, and Mechanical Properties of Spring Steel with Ultra-High Strength and Toughness

Shi,

Zheng,

Zhang

et al. 2024

Metals

View full text Add to dashboard Cite

In this research, a new type of spring steel with ultra-high strength and toughness was designed, and its mechanical properties and microstructure under different heat treatment processes were studied. The results show that the optimal heat treatment process for the steel is oil quenching at 890 °C for 40 min, followed by tempering at 400 °C for 1 h. Its mechanical properties have an optimal combination of 1865MPa tensile strength, a yield strength of 1662 MPa, an elongation of 11.5%, a cross-sectional shrinkage of 51.5%, and a Charpy impact energy of 43.7 J at room temperature. With increasing austenitizing temperature, the austenite grain size increases, the martensite lath becomes thicker, and the strength decreases. With increasing tempering temperature, the lath boundary of martensite becomes blurred, the strength decreases, and the plasticity improves. In addition, it was found that during tempering at higher temperature (450 °C), large particle inclusions and secondary cracks appeared in the fractured surface, and a large number of carbides precipitated, leading to the brittleness of tempered martensite.

show abstract

Section: Introductionmentioning

confidence: 99%

Heat Treatment Process, Microstructure, and Mechanical Properties of Spring Steel with Ultra-High Strength and Toughness

Shi,

Zheng,

Zhang

et al. 2024

Metals

View full text Add to dashboard Cite

show abstract

“…Macro segregation is the phenomenon in which the concentration of solute elements in the solid-liquid two-phase solubility differs, leading to a redistribution of elements during the solidification process and resulting in a concentration difference between the solidliquid two phases [4][5][6]. The formation of billet segregation is typically attributed to the solidification process.…”

Section: Introductionmentioning

confidence: 99%

Homogenization Path Based on 250 mm × 280 mm Bloom under Mixed Light and Heavy Presses: Simulation and Industrial Studies

Dang,

Wang,

Wang

et al. 2024

Metals

View full text Add to dashboard Cite

This study proposed a new method for homogenizing continuous casting blooms based on solidification simulation calculations and industrial tests. The text describes a theoretical analysis of the solidification route of a cast billet of high-carbon alloy steel (B300A) under different process conditions. It summarizes the changing law of different under-pressure process parameters and under-pressure efficiency. The text also presents a solution to the seriousness of center shrinkage defects in the continuous casting of a large square billet of high-carbon alloy steel with the synergistic control technology of mixed light and heavy mixing under pressure. The study indicates that the center carbon segregation index of a high carbon steel continuous casting billet is 1.05, with a carbon extreme difference of not more than 0.08% and a proportion of 98.4%. Additionally, the center shrinkage is not more than a 0.5 level with a proportion of 99.5%. Meanwhile, the internal quality of cast billets has been improved, allowing for the rolling of large-size bars with a low consolidation ratio. The pass rate for internal ultrasonic flaw detection using the GB/T4162A grade is now higher than 99.95%, significantly reducing process costs and improving production efficiency for continuous casting and rolling.

show abstract

Microstructural Control and Alloy Design for Improving the Resistance to Delayed Fracture of Ultrahigh-Strength Automotive Steel Sheets

Cited by 2 publications

References 54 publications

Heat Treatment Process, Microstructure, and Mechanical Properties of Spring Steel with Ultra-High Strength and Toughness

Heat Treatment Process, Microstructure, and Mechanical Properties of Spring Steel with Ultra-High Strength and Toughness

Homogenization Path Based on 250 mm × 280 mm Bloom under Mixed Light and Heavy Presses: Simulation and Industrial Studies

Contact Info

Product

Resources

About