2D materials enhancing tribological performance in bulk and composite coatings: a review

The tribological properties of materials, such as wear, scratch resistance, corrosion resistance, and surface hardness, are heavily influenced by surface conditions. Therefore, understanding tribological behavior is a significant challenge in surface engineering. Typically, this behavior is controlled by applying protective coatings or layers post-fabrication of bulk components or by adding secondary reinforcements during manufacturing to enhance the performance of utilized bulk materials. These secondary reinforcements, including self-lubricating particles, ceramic particles, can also be incorporated into coatings to form composite layers. Particularly, developing 2D materials exhibit significant potential as secondary reinforcements for boosting tribological performance in both bulk materials and coatings. However, there is a lack of comprehensive understanding regarding their role in wear resistance and their interface interactions with various metal, ceramic, and polymer matrices. Furthermore, the production methods for incorporating 2D reinforcements into these matrices are not well-documented. This review addresses these gaps by emphasizing the importance of tribology and clarifying the essential role of 2D materials in enhancing the tribological behavior of composites. It explores the interface connection between 2D materials and different matrices, and examines various production techniques used to integrate these materials into bulk and coatings. This comprehensive review aims to provide insights that will facilitate the development of advanced tribological solutions in surface engineering.