An experimental and numerical scrutiny of crashworthiness variables for square column with V-notch and groove initiators under quasi-static loading

Figures & data

Figure 1. Various crush zones defined in an automotive vehicle.

Figure 2. (a) Deformation pattern and (b) basic folding mechanism.

Table 1. Chemical composition of Al6063 aluminium alloy

Fe%	Si%	Mn%	Cu%	Ni%	Cr%	Ti%
0.345	0.362	0.067	0.072	<0.01	0.008	0.021
Sn%	V%	Co%	Zn%	Pb%	Mg%	Al%
0.003	0.0006	0.002	0.03	0.013	0.483	98.56

Figure 3. Test specimens of EHT, EHTV, EHTHG.

Figure 4. (a) Empty hollow tube (EHT), (b) Empty hollow tube V-notch (EHTV) and (c) Empty hollow tube horizontal groove (EHTHG).

Table 2. Physical material properties of Al6063 alloy

Parameter	Value	Units
Width	12.54	mm
Thickness	1.84	mm
Area	23.0736	mm^2
Initial gauge length	50	mm
Final gauge length	57.54	mm
Load at offset yield	2.536	KN
Peak load	3.473	KN
Tensile strength	150.5	MPa
0.2% Proof stress	109.924	MPa
% Elongation (50 mm GL)	15.08	%

Figure 5. Engineering stress -strain curve of Al6063 alloy.

Figure 6. UTM and specimen placed between the cross heads.

Figure 7. (a) Force–displacement curve and (b) Deformation modes of EHT, EHTV and EHTHG specimens with 5 mm/min.

Figure 8. (a) Force–displacement curve and (b) Deformation modes of EHT, EHTV and EHTHG specimens with 3.06 mm/s.

Table 3. Experimental results of EHT, EHTV and EHTHG for 5 mm/m

S. No.	Samples	Size (mm)	Thickness (mm)	Speed (mm/min)	Pmax (KN)	EA (kJ)	Mass (KG)	Pm (KN)	SEA (kJ/KG)	CFE (%)
(1)	EHT	50×50×250	2	5	26.779	2.4314	0.2613	13.89	9.3050	51.86
(2)	EHTV	50×50×250	2	5	27.416	2.0774	0.2596	12.355	8.0023	45.06
(3)	EHTHG	50×50×250	2	5	29.554	2.1621	0.2604	11.87	8.3029	40.16

Table 4. Experimental results of EHT, EHTV and EHTHG for 3.06 mm/s

S. No.	Samples	Size (mm)	Thickness (mm)	Speed (mm/s)	Pmax (KN)	EA (kJ)	Mass (KG)	Pm (KN)	SEA (kJ/KG)	CFE (%)
(1)	EHT	50×50×250	2	3.06	24.32	1.5914	0.2613	9.076	6.09	37.30
(2)	EHTV	50×50×250	2	3.06	20.16	2.0153	0.2596	11.766	7.76	58.27
(3)	EHTHG	50×50×250	2	3.06	22.59	2.1536	0.2604	12.534	8.27	55.48

Figure 9. (a) Peak force (P_max), (b) Energy absorption (EA), (c) Specific energy absorption (SEA), (d) Mean crush force (P_m) and (e) crush force efficiency (CFE) of EHT, EHTV and EHTHG specimens for 3.06 mm/s feed rate.

Figure 10. FE model of EHT, EHTV and EHTHG specimens.

Figure 11. Comparison of engineering stress-strain curve from tensile test with numerical modelling curve.

Figure 12. Deformation modes of EHT, EHTV and EHTHG specimens with 3.06 mm/s feed rate.

Figure 13. Numerical F–S data for EHT, EHTV and EHTHG specimens with 3.06 mm/s feed rate.

Table 5. Crashworthiness constants derived from FEM results for EHT, EHTV and EHTHG at 3.06 mm/s

S. No.	Samples	Size (mm)	Thickness (mm)	Speed (mm/s)	Pmax (KN)	EA (kJ)	Mass (KG)	Pm (KN)	SEA (kJ/KG)	CFE (%)
(1)	EHT	50×50×250	2	3.06	24.30	1.5500	0.2613	9.207	5.93	37.88
(2)	EHTV	50×50×250	2	3.06	18.63	1.8925	0.2596	11.147	7.29	59.83
(3)	EHTHG	50×50×250	2	3.06	21.26	1.9811	0.2604	11.560	7.60	54.37

Figure 14. Force–displacement curve for EHT.

Figure 15. Force–displacement curve for EHTV.

Figure 16. Force–displacement curve for EHTHG.

Table 6. Comparison of test and FEM results for EHT, EHTV and EHTHG specimen with 3.06 mm/s feed rate

S. No.	Samples	Size (mm)	Thickness (mm)	Speed (mm/s)	Pmax (KN)		EA (Kr)		Mass (KG)	Pm (1(N)		SEA (kJ/KG)		CFE (%)
					TEST	FEM	TEST	FEM		TEST	FEM	TEST	FEM	TEST	FEM
1	EHT	50×50×250	2	3.06	24.32	24.3	1.5914	1.55	0.2613	9.076	9.207	6.09	5.93	37.3	37.88
2	EHTV	50×50×250	2	3.06	20.16	18.63	2.0153	1.8925	0.2596	11.766	11.147	7.76	7.29	58.27	59.83
3	EHTHG	50×50×250	2	3.06	22.59	2126	2.1536	1.9811	0.2604	12.534	11.56	8.27	7.6	55.48	54.37

Figure 17. Test and FEM comparison of crashworthiness parameters (a) Peak force, (b) Energy absorption, (c) Specific energy absorption, (d) Mean crush force and (e) crush force efficiency of EHT, EHTV and EHTHG specimens for 3.06 mm/s feed rate.