EFFECT OF CONCENTRATION VARIATION OF TI ON MECHANICAL PROPERTIES OF FENICRCOTI HIGH ENTROPY ALLOY USING MOLECULAR DYNAMICS SIMULATION

• Main Author: Sophie Bintari, Olivia
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/85393
• Institution: Institut Teknologi Bandung

Various industries in the world require piping systems. However, pipe failure is often a hindrance in the development of piping systems, and one of the main causes is corrosion. FeNiCrCo alloy is one of the options for this pipe coating material. However, the hardness of the alloy is still not qualified and it is known that the addition of Ti to the alloy can increase it. This research was conducted to study the effect of Ti composition variation on the FeNiCrCoTi alloy using molecular dynamics simulation. Molecular dynamics simulations were conducted using LAMMPS to study the effect of varying Ti concentrations in the range of 0-20 at% at room temperature (300 K). Structural optimization was performed to obtain equilibrium lattice parameter values using Atomsk, followed by a uniaxial tensile test and calculation of the stacking fault energy (SFE) value. Microstructure evolution analysis using common neighbor analysis (CNA) and dislocation behavior in the alloy through dislocation analysis (DXA) were also conducted using OVITO to explain the impact of Ti addition on the mechanical properties of the alloy. The simulation results show that the lattice parameter value of equiatomic FeNiCrCoTi (3.695 Å) is higher than that of FeNiCrCo (3.538 Å). The UTS values for equiatomic FeNiCrCoTi and FeNiCrCo are 3.95 GPa and 16.08 GPa, respectively, while their elastic moduli are 104.37 GPa and 196.7 GPa, and their yield strengths are 3.9 GPa and 15.8 GPa. Equiatomic FeNiCrCoTi undergoes a structural change from FCC to amorphous and forms Shockley dislocations more rapidly than FeNiCrCo. The SFE value of FeNiCrCo is 69.19 mJ/m², while the SFE value of equiatomic FeNiCrCoTi is 9.54 mJ/m².