R&D: Graphene-Reinforced Amorphous Carbon Film for HAMR Head, Molecular Dynamics and Density Functional Theory Study

Materials Today Communications has published an article written by Qingkang Liu, Zhen Chen, Xiaohong Zhu, Kaihao Huang, Ziyue Wang, Hui Yang, Wenkai Wu, Liang Peng, and Yufei Hu, School of Energy and Mechanical Engineering, Jiangxi University of Science and Technology, Nanchang 330013, China.

Abstract: “Heat-assisted magnetic recording (HAMR) is technology which can extend the area density to 10 Tb/in². The high temperature at the head/disk interface (HDI) leads to lubricant degradation and transfer to the HAMR head. The friction characteristics and reliability of HAMR HDI are reduced. The graphene-reinforced amorphous carbon (a-C) film may be a potential coating for HAMR head. The molecular dynamics and density functional theory are used to investigate the adsorption and diffusion behaviors of lubricants on the graphene-reinforced a-C film. The thermal stability of graphene-reinforced a-C film is studied. As the temperature increases, D-4OH lubricants exhibit uniform sliding on the surface of graphene-reinforced a-C film. And the covalent bonds between the graphene and the a-C film are broken. The graphene-reinforced a-C film effectively prevents the decomposition of the lubricants. The graphene makes the surface of the a-C film electrically neutral, which improves the inertness and reduces the adsorption capacity of the D-4OH lubricant end groups. Compared to uncovered a-C film, the graphene-reinforced a-C film has better thermal stability. The graphene-reinforced a-C film with high thermal stability can minimize the adsorption and degradation of lubricants on the HAMR head, and improve the reliability of HAMR HDI.“