Preparation and Properties of High-Temperature Self-Lubricating Materials Based on H13 Steel

High-temperature self-lubricating materials based on H13 steel are prepared by the powder metallurgy method. The sintering process, phase addition and high-temperature testing of the material are studied so that the mechanical and wear performance of the composites can be optimized. The results show that the optimum sintering process is 2 h at a temperature of 1250 °C. When the contents of Cr₂C₃ and CaF₂ are 10%, the mechanical and sintering properties of the composites are acceptable. The relative density reaches 80.2% and the bending strength reaches 720.2 MPa. Moreover, CaF₂ effectively reduces the friction coefficient and wear rate of the material. The friction coefficient decreases to a minimum of 0.24, but the wear rate increases to a maximum of 7.26 × 10⁻⁵ mm²/min at a load of 1065 g. Cr₂C₃ helps to alleviate the oxidation of the composites, and the precipitation of CaF₂ causes network cracks to reduce the thermal fatigue performance.