Hot Stamping High Strength Steel Spot Welding Technology and Quality Evaluation of Welding Joint

2014 ◽  
Vol 1063 ◽  
pp. 181-185
Author(s):  
Su Feng Hao ◽  
Zhong De Shan ◽  
Shu Jun Chen ◽  
Chao Jiang
Keyword(s):  
High Strength Steel ◽  
Spot Welding ◽  
Quality Evaluation ◽  
Hot Stamping ◽  
High Strength ◽  
Interfacial Fracture ◽  
Welding Parameters ◽  
Local Cooling ◽  
Welding Joint ◽  
Pull Out

The heterogeneity of microstructure and mechanical performance of welding joints were affected by unique material properties such as high resistivity and low thermal conductivity, instantaneous high temperature of spot welding thermal cycle, and uneven local cooling rate. Because of ultra high strength of hot stamping parts, the welding joint is more inclined to fail as the failure mode of interfacial fracture, the traditional critical nugget formula fell down. Through designing orthogonal experiment, the effect of different welding parameters on joint performance was analyzed, the optimized welding process was obtained; on account of the quality evaluation of welding joint, nugget spherical mode was built to separately analyze the stress condition of welding joint in the failure modes of interfacial fracture and nugget pull-out, the new evaluation criterion aimed at high strength steel was established. Two kinds of 1.2 mm and 2.0 mm steels were used to validate the critical weld diameter. Results showed that the critical formula could accurately evaluate failure of the weld joints.

scholarly journals Effect of Severe Welding Conditions on Liquid Metal Embrittlement of a 3rd-Generation Advanced High-Strength Steel

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1166
Author(s):  
Outhmane Siar ◽  
Yacine Benlatreche ◽  
Thomas Dupuy ◽  
Sylvain Dancette ◽  
Damien Fabrègue
Keyword(s):  
Liquid Metal ◽  
High Strength Steel ◽  
Spot Welding ◽  
High Strength ◽  
Holding Time ◽  
Liquid Metal Embrittlement ◽  
Welding Parameters ◽  
Advanced High Strength Steel ◽  
Electrode Force ◽  
Influential Parameters

The occurrence of liquid metal embrittlement (LME) during the resistance spot-welding of a zinc-coated Advanced High-Strength Steel (TRIP-aided AHSS) is investigated in this work. Welds are generated using controlled degradation of the welding conditions to favor the occurrence of LME cracks in a two-sheets homogeneous configuration. Detailed inspection of the welds shows that electrode misalignment, short holding time, low electrode force and long welding time constitute a propitious environment for both inner and outer LME cracks. A statistical analysis allows weighting and interpreting of the significance of the welding parameters. Electrode misalignment and reduced holding time appear as the most influential parameters in the design of experiment. Moreover, it is worth noting that standard ISO welding conditions are prone to avoid any LME cracks in the investigated two-sheets homogeneous configuration.

Study on Resistance Spot Welding Technology and Properties of TRIP800 High Strength Steel Sheet

2011 ◽  
Vol 391-392 ◽  
pp. 661-665
Author(s):  
Yan Yu ◽  
Feng Xue Wang ◽  
Zai Dao Yang
Keyword(s):  
Mechanical Properties ◽  
High Strength Steel ◽  
Spot Welding ◽  
Welding Current ◽  
High Strength ◽  
Welding Parameters ◽  
Welding Time ◽  
Test Analysis ◽  
Welding Technology ◽  
Welding Electrode

A series of spot welding technology, joint mechanical properties and microhardness test analysis of TRIP800 high strength steel were researched. Based on these experiments and analysis, effect of spot welding parameters such as welding current, welding time and electrode pressure on joint mechanical properties were explored. The relevant spot welding parameters of TRIP800 high strength steel of spot welding were recommended, such as welding current is7.5~8.0KA, electrode pressure is 450 kgf and welding time is 20cyc. Welding electrode should be to ensure that as much as possible and clean the surface,to avoid welding current and welding time is too high or too long, as well as forging lack of power, to prevent the occurrence of welding defects.

Experiment Research on Tensile-Shear Behavior of Spot-Welded Lap Joints of Ultra-High Strength Steel with Common Steel

2013 ◽  
Vol 716 ◽  
pp. 266-270
Author(s):  
Xiang Li ◽  
Xiao Yang Li ◽  
Hui Ping Yu ◽  
Ya Li
Keyword(s):  
Base Metal ◽  
Heat Affected Zone ◽  
High Strength Steel ◽  
Spot Welding ◽  
Tensile Strain ◽  
High Strength ◽  
Weld Nugget ◽  
Tensile Shear ◽  
Welding Joint ◽  
Ultra High Strength Steel

The welding spot of Ultra-high strength steel of 22MnB5 and common steel of St16 were the investigative objects, the intermediate frequency inverter & electric servo welding system was used to weld the sheets. Electrical measuring test method was used on spot-welded joint under tensile-shear load to determinate the strain of different positions, including the strain of weld nugget, the stain around the nugget and the base metals strain near the weld nugget. The deformation regularity of spot welding joints surrounding and base metal were analysed according to the data. The test provided a reference for the numerical simulation of spot welding model. Test results show that the strain distribution on spot welding joint is not uniform, the strain of the weld nugget center is relatively small, large deformation exists mainly in the heat affected zone. That is to say, the area near the spot-welding joint heat affected zone is prone to yield. The base metal area near the weld nugget is mainly affected by tensile strain, and the strain increases with the increasing of the load. The force condition of the specimen is complicated around the nugget, the relationship between the load and the strain is erratic. The strain of the weld nugget will gradually change from axial compressive strain to axial tensile strain. The strain of spot welding specimen made of dissimilar materials (22MnB5& ST16) is negative, and almost linearly.

Quenchability improvement and control simplification by ice mandrel in hot stamping of ultra-high strength steel hollow parts

2021 ◽  
Vol 64 ◽  
pp. 916-926
Author(s):  
Ali Talebi-Anaraki ◽  
Tomoyoshi Maeno ◽  
Ryohei Ikeda ◽  
Kazui Morishita ◽  
Ken-ichiro Mori
Keyword(s):  
High Strength Steel ◽  
Hot Stamping ◽  
High Strength ◽  
Ultra High Strength Steel ◽  
And Control
Sign in / Sign up

Export Citation Format

Share Document