Processability and wide-temperature-range properties of MoS ₂ /PEEK self-lubricating composites manufactured by laser powder bed fusion process

To address the increasing demand for lightweight, highly friction- and wear-resistant, integrally designed moving components in aerospace applications, this study systematically investigated the processability and wide-temperature-range properties of the MoS2/polyether-ether-ketone (PEEK) self-lubricating composites fabricated using the laser powder bed fusion (LPBF) process. The results demonstrated that the incorporation of MoS2 enhanced powder flowability and thermal stability, albeit at the expense of laser absorptivity. Optimal processing parameters were established, achieving a porosity of less than 0.01%. Notably, adding MoS2 significantly influenced the crystallization behaviour of PEEK, leading to tensile strengths exceeding 92 MPa at both room and low temperatures, along with an elongation greater than 20% at 150°C. The coefficient of friction for the 12 wt.% MoS2/PEEK self-lubricating composite was measured at 0.035, 0.11, and 0.058 at temperatures of −150, 20, and 150°C, respectively, representing a reduction of over 75% compared to pure PEEK. Correspondingly, the wear rates indicated a reduction of more than 80%. Additionally, the fracture and wear mechanisms of pure PEEK and the MoS2/PEEK self-lubricating composites at extreme temperatures were revealed. This research lays a crucial foundation for the LPBF fabrication of self-lubricating polymer composites and advances their application within the aerospace industry.