Investigation of Iron in High Temperature Molten Liquid Lead Using the Lennard-Jones Potential

Abstract

Liquid metal corrosion is getting more attentions by nuclear material researchers. The information about corrosions and damages mechanism of nuclear structural materials are very important for nuclear reactor design. In this current work we study the corrosion of iron when immersed in liquid lead. We study the phenomena by molecular dynamics method based on the Lennard-Jones potential for interaction between two neutral atoms the material. The potential has two parameters i.e. collision parameterሺ𝜎ሻ and energy ሺ𝜀ሻ. We also study the iron corrosion inhibition by using nitrogen agent. To simulate the corrosion phenomena, we use the MOLDY molecular dynamics program. For doing this we need to verify the used Lennard-Jones potential parameters firstly. The verification is done by adjusting the two parameters (𝜎, 𝜀 till the value of diffusion coefficient (iron in liquid lead) is similar between simulation and experiment, under certain small error. The two parameters (𝜎, 𝜀 in this work after some correction should be the best value for studying corrosion inhibition or others. We got new parameter 𝜀 ൌ 0.4007𝑒𝑉 and𝜎 ൌ 2.3894Å for iron, while for lead 𝜀 ൌ 0.1910𝑒𝑉and 𝜎 ൌ 2.9578Å. By using these parameters in simulation of corrosion inhibition using nitrogen, we can make estimation that for reducing the iron corrosion, it is recommended if we inject nitrogen gas into liquid lead for about concentration of 0.29𝑤𝑡%for the best inhibition.

Liquid metal corrosion is getting more attentions by nuclear material researchers. The information about corrosions and damages mechanism of nuclear structural materials are very important for nuclear reactor design. In this current work we study the corrosion of iron when immersed in liquid lead. We study the phenomena by molecular dynamics method based on the Lennard-Jones potential for interaction between two neutral atoms the material. The potential has two parameters i.e. collision parameterሺ𝜎ሻ and energy ሺ𝜀ሻ. We also study the iron corrosion inhibition by using nitrogen agent. To simulate the corrosion phenomena, we use the MOLDY molecular dynamics program. For doing this we need to verify the used Lennard-Jones potential parameters firstly. The verification is done by adjusting the two parameters (𝜎, 𝜀 till the value of diffusion coefficient (iron in liquid lead) is similar between simulation and experiment, under certain small error. The two parameters (𝜎, 𝜀 in this work after some correction should be the best value for studying corrosion inhibition or others. We got new parameter 𝜀 ൌ 0.4007𝑒𝑉 and𝜎 ൌ 2.3894Å for iron, while for lead 𝜀 ൌ 0.1910𝑒𝑉and 𝜎 ൌ 2.9578Å. By using these parameters in simulation of corrosion inhibition using nitrogen, we can make estimation that for reducing the iron corrosion, it is recommended if we inject nitrogen gas into liquid lead for about concentration of 0.29𝑤𝑡%for the best inhibition.