Modeling of Material Orientation Effects on AHSS Crush and Fracture Behavior in Axial Crush Tests

Figures & data

Fig. 1 Geometry of the 12-sided design (color figure available online).

Table 1 Steel grades and material properties in L and T directions.

		Yield
		strength	Tensile	TE^a	n Value	Fracture
Material	Direction	(MPa)	strength (MPa)	(%)	(5/UE)	strain
HSLA340 (1.0 mm)	L	368	446	28.6	0.17	1.68
	T	394	450	27.4	0.16	1.36
DP590 (1.0 mm)	L	374	604	24.4	0.17	1.11
	T	389	608	22.7	0.16	0.94
DP590IBF (1.0 mm)	L	353	601	23.1	0.18	1.28
	T	365	605	24.7	0.18	1.16
DP780 (1.0 mm)	L	476	817	17.0	0.15	0.57
	T	482	840	15.4	0.14	0.42
DP780IBF (1.0 mm)	L	588	839	14.6	0.10	0.80
	T	612	864	14.6	0.09	0.70
TRIP780 (1.1 mm)	L	500	820	20.4	0.18	0.52
	T	501	822	20.4	0.17	0.54
^aTE = Total Elongation

Fig. 2 Comparisons of crack length (color figure available online).

Table 2 Comparison of crush load and crush distance

		Average crush	Crush distance
Material	Direction	load (kN)	(mm)
HSLA340 (1.0 mm)	L	54.3	226
	T	56.5	222
DP590 (1.0 mm)	L	66.3	185
	T	66.7	183
DP590IBF (1.0 mm)	L	68.1	178
	T	68.1	180
DP780 (1.0 mm)	L	71.2	171
	T	72.1	163
DP780IBF (1.0 mm)	L	81.4	147
	T	81.0	145
TRIP780 (1.1 mm)	L	87.6	137
	T	86.3	137

Fig. 3 Measured force–displacement curves for DP780 (color figure available online).

Fig. 4 Comparisons of tested deformation modes for DP780 (color figure available online).

Fig. 5 Optimization of the extension of stress–strain curve in the transverse direction (color figure available online).

Fig. 6 Load curves from uniaxial tension tests on DP780 in the transverse direction (color figure available online).

Fig. 7 Optimized extension of the stress–strain curve for DP780 in the transverse direction (color figure available online).

Fig. 8 Estimated fracture locus for DP780 (color figure available online).

Fig. 9 Comparison of predicted force–displacement curves for DP780: (a) L direction and (b) T direction (color figure available online).

Fig. 10 Comparison of predicted deformation modes for DP780: (a) MAT224, L direction, (b) MAT224, T direction, (c) MAT103, L direction, and (d) MAT103, T direction (color figure available online).