Mechanical Properties and Microstructure of High-Strength Steel Controlled by Hot Stamping Process

2018 ◽  
Vol 27 (8) ◽  
pp. 4025-4035 ◽  
Author(s):  
Hang Ou ◽  
Xu Zhang ◽  
Junrui Xu ◽  
Guangyao Li ◽  
Junjia Cui
Keyword(s):  
Mechanical Properties ◽  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Stamping Process

scholarly journals Integrated Modelling of Microstructure Evolution and Mechanical Properties Prediction for Q&P Hot Stamping Process of Ultra-High Strength Steel

2020 ◽  
Vol 33 (1) ◽  
Author(s):  
Yang Chen ◽  
Huizhen Zhang ◽  
Johnston Jackie Tang ◽  
Xianhong Han ◽  
Zhenshan Cui
Keyword(s):  
Mechanical Properties ◽  
Microstructure Evolution ◽  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Carbon Partitioning ◽  
Integrated Modelling ◽  
Finite Element Software ◽  
Stamping Process ◽  
Mechanical Properties Prediction

Abstract High strength steel products with good ductility can be produced via Q&P hot stamping process, while the phase transformation of the process is more complicated than common hot stamping since two-step quenching and one-step carbon partitioning processes are involved. In this study, an integrated model of microstructure evolution relating to Q&P hot stamping was presented with a persuasively predicted results of mechanical properties. The transformation of diffusional phase and non-diffusional phase, including original austenite grain size individually, were considered, as well as the carbon partitioning process which affects the secondary martensite transformation temperature and the subsequent phase transformations. Afterwards, the mechanical properties including hardness, strength, and elongation were calculated through a series of theoretical and empirical models in accordance with phase contents. Especially, a modified elongation prediction model was generated ultimately with higher accuracy than the existed Mileiko’s model. In the end, the unified model was applied to simulate the Q&P hot stamping process of a U-cup part based on the finite element software LS-DYNA, where the calculated outputs were coincident with the measured consequences.

scholarly journals Study on Phase Transformation in Hot Stamping Process of USIBOR® 1500 High-Strength Steel

Metals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1119 ◽  
Author(s):  
Pengyun Zhang ◽  
Le Zhu ◽  
Chenyang Xi ◽  
Junting Luo
Keyword(s):  
Phase Transformation ◽  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Transformation Kinetics ◽  
Martensite Content ◽  
Cct Curve ◽  
Stamping Process ◽  
Quenching Process ◽  
Kinetics Of

Based on the Kirkaldy-Venugopalan model, a theoretical model for the phase transformation of USIBOR® 1500 high strength steel was established, and a graph of the phase transformation kinetics of ferrite, pearlite, and bainite were plotted using the software MATLAB. Meanwhile, with the use of the software DYNAFORM, the thermal stamping process of an automobile collision avoidance beam was simulated. The phase transformation law of USIBOR® 1500 high-strength steel during hot stamping was studied through a simulation of the phase transformation during the pressure holding quenching process. In combination with the continuous cooling transformation (CCT) curve, the cooling rate of quenching must be greater than 27 °C/s to ensure maximum martensite content in the final parts, and the final martensite content increases as the initial temperature of the sheet rises.

Hybrid quenching method of hot stamping for automotive tubular beams

2015 ◽  
Vol 231 (9) ◽  
pp. 1599-1610 ◽  
Author(s):  
Jong-Kyu Park ◽  
Yang-Su Kim ◽  
Chang Hee Suh ◽  
Young-Suk Kim
Keyword(s):  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Torsion Beam ◽  
Stamping Process ◽  
Die Quenching ◽  
Ultra High Strength Steel ◽  
Quenching Method ◽  
Torsion Beam Axle ◽  
Beam Axle

Recently, tubular-type coupled torsion beam axle, which is a component of the automotive rear suspension systems, has been developed by using ultra-high strength steel. It is manufactured by hot stamping process to enhance the strength and reduce springback. The hot stamping process is classified as a direct method and an indirect method according to forming sequence and quenching method, so-called die quenching or water quenching. Each of these methods has limitations in the aspect of dimensional accuracy and strength. Hybrid quenching is a new quenching method which sprays water to the tube directly in addition to die quenching. In this study, direct hot stamping with hybrid quenching was applied to produce an automotive tubular coupled torsion beam axle of ultra-high strength steel. This study proposes a simulation method of hybrid quenching for tubular beam and the hybrid quenching method was evaluated experimentally. Finally, the proposed hybrid quenching method has been found very effective in reducing the cooling time and thermal deformation.

Hot Stamping of Two Different High Strength Steel with Tailored Properties

2013 ◽  
Vol 395-396 ◽  
pp. 909-913 ◽  
Author(s):  
Zi Jian Wang ◽  
Ya Xu ◽  
Wen Ting He ◽  
Yi Sheng Zhang
Keyword(s):  
Mechanical Properties ◽  
High Strength Steel ◽  
Motor Vehicle ◽  
Hot Stamping ◽  
High Strength ◽  
Air Gap ◽  
Heating Zone ◽  
Cooling Zone ◽  
Widespread Application ◽  
Transition Zones

With the increasingly widespread application of high-strength steel (HSS), tailored properties, namely different mechanical properties required in different regions of the same part, have been proposed, in order to achieve the matching between mechanical properties and safety performance of motor vehicle parts. In this paper, the influence of air gap on the final hardness and strength distribution is discussed in terms of two different HSS, namely LG1500HS and WHT1500HF. As for steel LG1500HS, regardless of the location of samples in the formed part, the final fracture area is in the vicinity of the air gap center, proving the lowest hardness and strength in transition zones. Compared to steel LG1500HS, steel WHT1500HF exhibits gradient hardness distribution from the cooling zone to the heating zone, with no minimal value discovered in transition zones.

scholarly journals Research on Lightweight Design and Indirect Hot Stamping Process of the New Ultra-High Strength Steel Seat Bracket

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 833 ◽  
Author(s):  
Tang ◽  
Gu ◽  
Jia ◽  
Li ◽  
Zhu ◽  
...  
Keyword(s):  
Topology Optimization ◽  
High Strength Steel ◽  
Lightweight Design ◽  
Hot Stamping ◽  
High Strength ◽  
Variable Density ◽  
Stamping Process ◽  
Electric Bus ◽  
Ultra High Strength Steel ◽  
New Type

Aiming at the need for lightweight requirements of the electric bus components, combined with the performance advantages of the hot stamping ultra-high strength steel, a new type of seat bracket structure is proposed. The new structure was analyzed by finite element method and the variable density topology optimization results. Subsequently, the new seat bracket was manufactured by the indirect hot stamping process. The results showed that the new type of seat bracket can reduce the weight by 17.04% after topology optimization, which achieved the goal of lightweight design of the structure. After indirect hot stamping, the bottom of the seat bracket microstructures were mainly martensite and the ultimate tensile strength was about 1560 MPa, the microhardness was equally distributed at about 513.5 HV. Finally, according to the stiffness check test, the seat bracket satisfied the user requirements.

Sign in / Sign up

Export Citation Format

Share Document