Hot Forming Analysis of Car Door Bar for Ultra High Strength Steel

2010 ◽  
Vol 160-162 ◽  
pp. 836-841
Author(s):  
Yun Kai Gao ◽  
Da Wei Gao ◽  
You Zhi Deng ◽  
Wei Cao
Keyword(s):  
High Strength Steel ◽  
Thickness Distribution ◽  
High Strength ◽  
Simulation Method ◽  
Hot Forming ◽  
Forming Limit ◽  
Boron Steel ◽  
Shell Elements ◽  
Forming Simulation ◽  
Ultra High Strength Steel

Ultra high strength steel plays an important role of light weighting in automotive industry. The hot forming simulation of car door bar is processed with 22MnB5 ultra high strength boron steel. FEM is built with the 12 nodes shell elements and MAT 106 is selected in LS-DYNA. The hot forming processes include two heat transfers. One is the process from the oven to the tools after the blank is heated. The other is the process after the blank contacts the tools. The hot forming simulation results are obtained by LS-DYNA. The results show that the thickness distribution, the forming limit and the maximum effective plastic strain and other performances attain to standards. It is proved that the hot forming simulation method is correct.

Influences of Variable Friction Coefficient on the Hot Formability of Ultra High Strength Steel Sheet

2010 ◽  
Vol 154-155 ◽  
pp. 1450-1455
Author(s):  
Hai Yan Yu ◽  
Li Bao ◽  
You Zhi Deng ◽  
Wei Cao
Keyword(s):  
Friction Coefficient ◽  
High Strength Steel ◽  
Steel Sheet ◽  
Coupling Effect ◽  
High Strength ◽  
Hot Forming ◽  
Forming Simulation ◽  
Ultra High Strength Steel ◽  
Variable Friction ◽  
The One

Friction coefficient is an important parameter in sheet metal forming especially in hot forming. Friction condition not only influences material flow but also affects the thermal conductivity between blank and tools. In this study, varied friction coefficient is introduced to the hot forming simulation of B-pillar made of ultra high strength steel sheet 22MnB5. Three curves of friction coefficient vs. temperature are investigated. All of the heat transferred by conductivity, radiation and convection are considered in the simulation. And the temperature-dependent material and process parameters are supplied. It is demonstrated that the coupling effect among the strength and hardness of the metals, the properties of the oxide film covering blank surface and viscosity of the lubrication oil leads to the fact that the friction coefficient changes with temperature instead of constant during hot forming. The friction coefficient curve characterized by increasing first then decreasing gives the best simulation results and then is followed by the one which is characterized by decreasing first then increasing. The constant friction coefficient is the last.

Hot Forming Technique and Its Equipments for Ultra High Strength Steel

2010 ◽  
Author(s):  
Ning Ma ◽  
Ping Hu
Keyword(s):  
High Strength Steel ◽  
Chemical Engineering ◽  
Cooling System ◽  
High Strength ◽  
Hot Forming ◽  
Continuous Heating ◽  
Step Method ◽  
Three Point Bending ◽  
Ultra High Strength Steel ◽  
One Step

Hot forming of ultra high strength steel is an advanced forming technique which can not only represent the best solution to increasing the strength-to-mass ratio of sheet components, but also meet the need of higher passive safety and weight reduction. Based on independently developed mass production line of hot forming, its key forming and quenching technique and relative equipments are proposed and described, including multi-step and one-step method, die manufacturing with cooling system, continuous heating furnace and integrated manufacturing system composed of the advanced interdisciplinary technology of machining, electronic control, material and chemical engineering. Then the automobile body components are produced by the developed equipments of hot forming and moreover their mechanical properties are investigated. The typical tensile curve of the quenched components shows that the yield stress of the hot forming component is over 1000MPa, and the strength limitation is over 1600MPa. The three-point bending testing of the part is implemented. These experimental results indicate the validity of the developed technique and equipments.

Forming Response of Ultra High Strength Steel Sheet to Stamping Speed during Hot Forming

2010 ◽  
Vol 160-162 ◽  
pp. 123-129 ◽  
Author(s):  
Hai Yan Yu ◽  
Li Bao ◽  
You Zhi Deng ◽  
Wei Cao
Keyword(s):  
Temperature Field ◽  
Steel Sheet ◽  
Coupling Effect ◽  
High Strength ◽  
Hot Forming ◽  
Boron Steel ◽  
Cold Forming ◽  
22Mnb5 Steel ◽  
Ultra High Strength Steel ◽  
Shaped Part

Stamping speed is an important parameter in sheet metal forming especially in hot forming. In this study, hot forming of a U-shaped part made of ultra high strength boron steel (22MnB5) sheet is simulated with solid elements. The mechanical properties of 22MnB5 steel sheet and the key process parameters are introduced in detail. Emphasis is laid on the forming response of the boron steel sheet to stamping speeds of 3.25m/s, 0.325m/s and 0.0325m/s. The mechanism of stamping speed acting on hot formability and temperature field of the stamped part is analyzed. It is demonstrated that stamping speed affects both formability and the heat transferred from blank to tools and to environment during hot forming. And the coupling effect of material properties, the heat produced during plastic deformation and heat boundary condition decides the formability and temperature field. An appropriate stamping speed is more important for hot forming than that for common cold forming.

Analysis of the Design and Mechanical Performance about Hot Stamping Power Fitting Products

2014 ◽  
Vol 1063 ◽  
pp. 272-275 ◽  
Author(s):  
Ming Lin Zhou ◽  
Liang Wang ◽  
Zi Jian Wang ◽  
Yi Lin Wang ◽  
Yi Sheng Zhang
Keyword(s):  
Transmission Line ◽  
Manufacturing Process ◽  
Mechanical Performance ◽  
Hot Stamping ◽  
Electrical Power ◽  
High Strength ◽  
Simulation Method ◽  
Boron Steel ◽  
Ultra High Strength Steel ◽  
Design And Manufacturing

Hot stamping ultra-high strength steel not only plays an important role in automotive field, but also has potential application in transmission line fittings industry. According to the current development status of Chinese electrical power fittings and the demand for new technique, combined with hot stamping technology, a new solution for reduction of weight in transmission line fittings has been proposed. This paper focuses on a new lightweight connection fitting with multilayer stack structure of ultra-high strength boron steel, and the key issue in design and manufacturing process of the deep U-shaped hot stamping stacked steel sheet. Numerical simulation method combining the experimental data is also used to predict mechanical performance of the new connection fitting, which provides guidance for the manufacturing process.

Sign in / Sign up

Export Citation Format

Share Document