scholarly journals Study on the prediction of tensile strength and phase transition for ultra-high strength hot stamping steel

2020 ◽  
Vol 9 (6) ◽  
pp. 14244-14253
Author(s):  
Shuang Liu ◽  
Mujun Long ◽  
Siyuan Zhang ◽  
Yan Zhao ◽  
Jingjun Zhao ◽  
...  
Keyword(s):  
Phase Transition ◽  
Tensile Strength ◽  
Hot Stamping ◽  
High Strength ◽  
Hot Stamping Steel

scholarly journals Evolution of Phase Transition and Mechanical Properties of Ultra-High Strength Hot-Stamped Steel During Quenching Process

Metals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 138 ◽  
Author(s):  
Shuang Liu ◽  
Mujun Long ◽  
Songyuan Ai ◽  
Yan Zhao ◽  
Dengfu Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Phase Transition ◽  
Cooling Rate ◽  
Hot Stamping ◽  
Coupled Model ◽  
High Strength ◽  
Austenitizing Temperature ◽  
Stamping Process ◽  
Quenching Process ◽  
Hot Stamping Steel

Hot stamping process is widely used in the manufacture of the high strength automotive steel, mainly including the stamping and quenching process of the hot-formed steel. In the hot stamping process, the steel is heated above the critical austenitizing temperature, and then it is rapidly stamped in the mold and the quenching phase transition occurs at the same time. The quenching operation in the hot stamping process has a significant influence on the phase transition and mechanical properties of the hot-stamping steel. A proper quenching technique is quite important to control the microstructure and properties of an ultra-high strength hot-stamping steel. In this paper, considering the factors of the austenitizing temperature, the austenitizing time and the cooling rate, a coupled model on the thermal homogenization and phase transition from austenite to martensite in quenching process was established for production of ultra-high strength hot-stamping steel. The temperature variation, the austenite decomposition and martensite formation during quenching process was simulated. At the same time, the microstructure and the properties of the ultra-high strength hot-stamping steel after quenching at different austenitizing temperature were experimental studied. The results show that under the conditions of low cooling rate, the final quenching microstructure of the ultra-high strength hot-stamping steel includes martensite, residual austenite, bainite and ferrite. With the increase of the cooling rate, bainite and ferrite gradually disappear. While austenitizing at 930 °C, the tensile strength, yield strength, elongation and strength-ductility product of the hot-stamping steel are 1770.1 MPa, 1128.2 MPa, 6.72% and 11.9 GPa%, respectively.

Ultra-High Strength Steel Hot Stamping Technology and Devices

2014 ◽  
Vol 1063 ◽  
pp. 237-243
Author(s):  
Zhong De Shan ◽  
Qin Tai Yan ◽  
Chao Jiang ◽  
Wen Juan Rong
Keyword(s):  
Tensile Strength ◽  
High Strength Steel ◽  
Hot Stamping ◽  
Research Work ◽  
High Strength ◽  
Parameters Optimization ◽  
Systematic Research ◽  
China Academy ◽  
Ultra High Strength Steel ◽  
Vehicle Structure

Ultra High Strength Steel (UHSS) hot stamping technology is a special process which can enhance the steel tensile strength to 1500MPa. Appling this technology in producing vehicle structure parts can make car lighter and safer. In China there are more and more automobile enterprises adopt this technology. To master and extend the skill, China Academy of Machinery Science & Technology (CAM) have done systematic research, such as the strengthen mechanism of the steel, hot stamping key devices designing, forming and quenching integrated mould designing, stamping process parameters optimization, etc.. By now, CAM has mastered the mass production technology of vehicle parts, which can guarantee its shape and tensile strength, and produced such typical parts as door-beam, B pillar, etc.. The paper is an introduction of the research work and achievement about UHSS hot stamping developed by CAM.

Warm Stamping of the 3rd Generation Sheet Steel for Automobiles

2014 ◽  
Vol 1063 ◽  
pp. 219-222 ◽  
Author(s):  
Han Dong ◽  
Cun Yu Wang ◽  
Ying Chen ◽  
Wen Quan Cao
Keyword(s):  
Cooling System ◽  
Hot Stamping ◽  
Sheet Steel ◽  
Surface Oxidation ◽  
High Strength ◽  
Advantages And Disadvantages ◽  
Forming Technology ◽  
New Type ◽  
Automobile Parts ◽  
Hot Stamping Steel

The advantages and disadvantages of the conventional hot stamping steel and the hot tamping technology were shortly reviewed. It was proposed that new type steel with relative low austenization temperature and air hardening ability should be designed and produced to overcome the surface oxidation and avoid the complexity of cooling system of the stamping dies. In this study, it was shown that the 3rd generation sheet steel with medium-Mn composition could be austenized and pressed at 700-750°C and air cooled into automobile parts with strength no less than 1.5GPa and ductility larger than 12%. This new steel and corresponding forming technology were called warm stamping technology, which overcomes the disadvantages of the conventional hot stamping steel. The fabrication trials of the automobile parts in the automobile industries were demonstrated with high strength and relative good ductility. It was concluded that the 3rd generation sheet steel and the warm stamping technology could be applied to replace the conventional hot stamping steel and conventional hot stamping technology in near future.

Simulation Study on the Austenisation and Cooling Behaviors of the Medium-Mn Steel

2014 ◽  
Vol 1063 ◽  
pp. 3-6 ◽  
Author(s):  
Si Lian Chen ◽  
Yao Zong Bao ◽  
Han Dong ◽  
Wen Quan Cao
Keyword(s):  
Tensile Strength ◽  
Chemical Composition ◽  
Hot Stamping ◽  
Total Elongation ◽  
Air Cooling ◽  
Car Industry ◽  
Medium Mn Steel ◽  
Hot Stamping Steel ◽  
Mn Steel ◽  
Holding Temperature

The austenisation and quenching behaviors of a medium-Mn steel with a chemical composition of C 0.14% and Mn 5.0% were presented in this paper. The heating and holding temperature varied from 500OC to 950OC was applied to find the austenization temperature. The holding time varied from 1-5minutes was used to choose the suitable austenisation time. Air cooling were applied to check the hardening capacity of the studied steel. It was found that the tensile strength is lower than 900Mpa and total elongation varied from 20-30% when the austenisation temperature is lower than 700OC. However, the tensile strength could be high up to 1600MPa and the total elongation about 12% when the austenisation temperature is higher than 700OC with air cooling. Based on the low austenisation temperature and the air hardening capacity, it was proposed that the studied medium-Mn steel could be used as the hot stamping steel in the car industry.

Martensitic Stainless Steel as Alternative for Hot Stamping Steel with High Product of Strength and Ductility

2014 ◽  
Vol 1063 ◽  
pp. 37-41
Author(s):  
Li Jun Wang ◽  
Chun Ming Liu
Keyword(s):  
Stainless Steel ◽  
Martensitic Stainless Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Processing Parameters ◽  
Shape Accuracy ◽  
Quenching And Partitioning ◽  
Automobile Components ◽  
Hot Stamping Steel ◽  
Strength And Ductility

Though more and more structural and safety automobile components are manufactured using hot stamping technology for the advantage of excellent shape accuracy while producing ultra high strength parts without any springback.Fewer hot stamping steels are developed except 22MnB5 steel, which exhibits ultra-high strength but limited ductility. Inspired by the application of quenching and partitioning C-Mn-Si steel, the microstructure and properties of a 30Cr13 steel subjected to quenching and partitioning treatment were studied to evaluate the possibility of martensitic stainless steel as alternative for hot stamping steel with high product of strength and ductility. The experiment result shows that, enhanced mechanical properties of Rel=1350MPa, Rm=1740MPa, and A=17.5% can be achieved through appropriate treatment. Due to the unique phase transformation conditions of martensitic stainless steel, processing parameters and corresponding equipments for automobile components manufacturing have to been investigated.

Simulation research of hot stamping and phase transition of automotive high strength steel

2011 ◽  
Vol 15 (sup1) ◽  
pp. s426-s430 ◽  
Author(s):  
B Zhu ◽  
Y‐S Zhang ◽  
J Li ◽  
H Wang ◽  
Z‐C Ye
Keyword(s):  
Phase Transition ◽  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Simulation Research

Hole-flange forming of high-strength steel sheet using one-step hot stamping-forging method

2016 ◽  
Vol 231 (1) ◽  
pp. 181-185 ◽  
Author(s):  
Fang-Sung Cheng
Keyword(s):  
Tensile Strength ◽  
High Strength Steel ◽  
Steel Sheet ◽  
Hot Stamping ◽  
High Strength ◽  
Successful Completion ◽  
Steel Sheets ◽  
One Step ◽  
Flange Forming ◽  
Hole Flanging

A process of one-step hot stamping-forging for increasing the tensile strength of the hole-flanging of the high-strength steel sheets with flange thickening was developed. In this proposed method, the high-strength steel sheet is directly formed within the designed die, which is simultaneously accompanied with a resistance heating, a hole punching, and the flanging and forging processes. The electrode material is SKD61. This material is not only used as the forming of the high-strength steel sheet but also directly served as the heating of the high-strength steel sheet within the die. The experimental results indicated that the high-strength steel sheet could be heated to 850 °C in 30 s by the SKD61 die. It demonstrates the successful completion of heating, hole punching, flanging and forging in a one-step process. Furthermore, it is found that the tensile strength of M18 tapped hole with forged part is increased by about 7.4% than that without forged part, and the breaking toughness is increased by about 33%.

Investigation on Properties and Microstructure in Hot Stamping Operation of Rear Axle Beams

2014 ◽  
Vol 1063 ◽  
pp. 143-147
Author(s):  
Xiao Chun Jin ◽  
Yong Shen Xue ◽  
Qing Nan Ma ◽  
Mei Zhang ◽  
Lin Li
Keyword(s):  
Automotive Industry ◽  
Rear Axle ◽  
Heating Temperature ◽  
Hot Stamping ◽  
High Strength Steels ◽  
High Strength ◽  
Basic Knowledge ◽  
Boron Steel ◽  
Temperature Boundary ◽  
Hot Stamping Steel

In the automotive industry, the hot forming of high strength steels offers the possibility to obtain significant reduction of weight without affecting the structural performances of final products. The main reason of its restricted application in the industry lies however in the lack of basic knowledge about mechanical and microstructural characteristics of sheets at elevated temperature, boundary conditions, and other process parameters. To partially overcome this limitation, this paper presents a research on the material properties of the hot stamping steel 22MnB5. Sheets of boron steel 22MnB5 with a thickness of 3.8mm were investigated and the results of experimental hot stamping tests were considered. The yield strength (YS) reached about 1200MPa, tensile strength (TS) reached 1500MPa, microhardness reached over 450HV at heating temperature of 880°C and holding 5 min.

Sign in / Sign up

Export Citation Format

Share Document