PSI - Issue 41

Muhammad Arif Husni Mubarok et al. / Procedia Structural Integrity 41 (2022) 282–289 Mubarok et al. / Structural Integrity Procedia 00 (2022) 000–000

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There are various materials and shapes that can be used as energy-absorbing structures. Mild steel is a ferrous metal made of iron and carbon. It is a low-cost material with properties suitable for most engineering applications. Steel exhibits the behavior of a ductile and stable plastic mechanism and provides a controlled and stable failure mode during the impact energy absorption process (Wierzbicki and Abramowicz, 1983). The material chosen in this numerical simulation is mild steel. Mild steel with E = 203 GPa, = 0.3 and = 7850 kg/m 3 was selected. Iqbal et al. (2015) have characterized mild steel, and all material parameters in the Johnson-Cook elastoplastic model were evaluated. The constants A , B , n , C , m , and Ɛ 0 are material-dependent parameters and may be determined from an empirical fit of flow stress data. The parameters obtained were validated using finite element simulation in ABAQUS.

Table 1. Material properties for Mild steel as obtained by Iqbal et al. (2015) Description Notation

Numerical Value

Yield Stress (MPa)

304.33 422.007

A B

Strain Hardening Constant (MPa) Strain Hardening Coefficient (-)

0.345

n

Strain-rate Hardening (-)

0.0156

C m Ɛ 0

Thermal Softening Constant (-) Reference Strain Rate Melting Temperature (K) Transition Temperature (K) Fracture Strain Constant (-)

0.87

0.0001 s

-1

1800

θ melt

293

θ transition

0.1152 1.0116 -1.7684 -0.05279

D 1 D 2 D 3 D 4 D 5

0.5262

The results show the comparison of the midpoint displacement value from the numerical simulation that we did with the numerical simulation results taken from Ref (Markose and Rao, 2017), presented in Figure 5.

0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 Displacement (m)

.01 Present Study .02 Present Study

.01 (Ref) (Markose & Rao, 2017) .02 (Ref) (Markose & Rao, 2017)

0.000

0.002

0.004

0.006

0.008

Time (s)

Fig. 5. Comparison of numerical results of lower face Time-Displacement from the center of the plate with Ref. (Markose and Rao, 2017) .

3. Numerical Analysis There are three variations of the core model of sandwich panels simulated in this paper. They are Honeycomb, Stiffener, and Corrugated with thickness adjusting structural weight ratio. Table 2 shows the geometric description of the core plate. In this paper, the structures are designed and analyzed in Mild Steel. The material is applied to the product and simulated as expected to compare existing models.