Table 1

Chemical composition of DP980 high-strength steel"

Fig.1

Comparison of stress-strain curves between longitudinal joint and base metal"

Fig.2

Schematic diagram of mixing rule"

Fig.3

Distribution curve of microhardness"

Fig.4

Comparison of fitting results in different regions of welded joints"

Fig.5

Grid division diagram of welding joint"

Fig.6

Comparison diagram of load displacement curve of simulation and test of optimal parameters of longitudinal joints"

Fig.7

Schematic diagram of discrimination"

Fig.8

Tensile testing and crack initiation in notched specimens"

Fig.9

Comparison of error between predicted value and real value"

Fig.10

Evolution diagram of genetic algorithm"

Table 2

Optimization results of genetic algorithm"

Fig.11

Comparison of load displacement curves of longitudinal joint shear model simulation and test"

Fig.12

Comparison of tensile and test cracks of longitudinal joint notch specimen"

Fig.13

Cupping test results and crack propagation direction"

Fig.14

Cupping test model"

Fig.15

Stress cloud of cupping test"

Fig.16

Variation law of hole volume fraction with stamping depth"

Fig.17

Comparison between cupping test and simulation curves"