Chen, Zan Wei, Xubing Lu, Shiqi Ding, Jiaqing Du, Naizhou Feng, Cunao Chen, Kai Guo, Peng Lee, Kwang-Ryeol Zhang, Guangan Li, Xiaowei 2025-08-20T04:31:04Z 2025-08-20T04:31:04Z 2025-08-20 2025-06 2223-7690 https://pubs.kist.re.kr/handle/201004/152967 Surface graphitization is an effective method for improving the friction performance of amorphous carbon (a-C) films. However, traditional modified methods, such as metal catalysis, addition of extra graphite or graphene, and annealing, often have drawbacks, such as complex operation, structural damage to the graphitized layer and intrinsic a-C films. In this study, a novel approach is explored to achieve in- situ surface graphitization of a-C films by short-term laser irradiation. In particular, as a key parameter, the influence of laser irradiation power on the surface graphitization structure and the mechanical and tribological properties of a-C films was emphasized. The results indicate that surface in- situ graphitization is successfully obtained on the surface of a-C films by laser irradiation and the surface graphitization degree is positively correlated with the laser irradiation power. Importantly, an obviously curled graphene structure is formed on the a-C films after laser irradiation. Compared with those of the intrinsic a-C film, the hardness and elastic modulus of the graphitized film surface obviously decrease after laser irradiation but without significantly deteriorated internal mechanical properties of the a-C film and also decrease gradually with increasing laser power, which is related to the increase in the sp(2)-C structure. Notably, in- situ surface graphitization induced by laser irradiation obviously reduces friction, which can be reduced by 25.41% compared with the intrinsic a-C film. This is attributed to the fast formation of the graphitized transfer film, which facilitates the transition of the friction interface from graphitized a-C surface/Al2O3 to graphitized a-C surface/graphitized transfer film. English Springer International Publishing AG Surface in-situ graphitization and properties of amorphous carbon film induced by laser irradiation Article 10.26599/FRICT.2025.9440977 1 Friction, v.13, no.6 Friction 13 6 Y scie 001532170600011 2-s2.0-105006626398 Engineering, Mechanical Engineering Article TRIBOLOGICAL PROPERTIES MECHANICAL-PROPERTIES GRAPHITE HARD FRICTION MICROSTRUCTURE RAMAN surface modification amorphous carbon (a-C) film laser-induced in-situ graphitization friction reduction solid lubrication