To address the problems of the difficult processing and internal microstructure disorder of porous bearing cages, Polyetheretherketone (PEEK) porous self-lubricating bearing cage material was prepared based on a fused deposition molding (FDM) process, and the porous samples were heat-treated on this basis, the research was carried out around the synergistic design of the material preparation, microstructure, and tribological properties. The results show that the pore size of the PEEK porous material prepared by the FDM process meets the requirements of the porous bearing cage; the samples with higher porosity also have higher oil content, and all the samples show high oil retention. Under dry friction conditions, the higher the porosity of the porous material, the larger the friction coefficient, and the friction coefficients of each sample after heat treatment show the same pattern; under starved lubrication conditions, the friction coefficient of the porous PEEK material decreased significantly compared to the compact PEEK material, showing a better self-lubrication effect, and the porous samples reached the best self-lubrication effect after heat treatment. The optimal process parameters were 60% mass fraction of NaCl, 40% mass fraction of PEEK, and the applied heat treatment process.

To meet the self-lubricating performance requirements of aerospace bearing cages, poly-ether-ether-ketone (PEEK)-based self-lubricating bearing cage materials were prepared based on the Fused Deposition Molding (FDM) process. The mechanical and tribological properties under high temperature condition (200°C) of the porous self-lubricating materials were researched. The results of microstructure analysis of porous sample showed that under laboratory conditions, NaCl can exhibit excellent pore-forming effect and could be effectively removed. The mechanical test results showed that the mechanical properties of the samples showed a significant decrease with the increase in porosity, and were affected by the synergistic effect of pore creation. However, the mechanical properties of heat-treated samples can meet the performance requirements of the bearing cage. The results of the tribological performance tests under high temperature conditions showed that the wear process of the dense samples was more smoother. Further comparing with the tribological properties at room temperature, it was found that the wear resistance of PEEK samples decreased under high temperature conditions. The normalized results of the mechanical and tribological properties data show that the samples with 50 wt% of porogenic agent can express the most balanced and excellent overall performance.

Porous composites utilize their unique pore structures to effectively store and release lubricants, providing a fundamental mechanism for continuous lubrication in self-lubricating bearing cages. This study investigates carbon nanotube (CNT)-reinforced PEEK porous composites fabricated by fused deposition modeling (FDM) and subsequently subjected to heat treatment to improve tribological properties. Results show that incorporating 3 wt% CNTs significantly enlarges average pore size from 0.08 μm to 11.62 μm and increases porosity, resulting in an oil retention rate exceeding 80%. The composites achieve a 26.4–63.4% reduction in friction coefficient under dry sliding conditions at room temperature. After heat treatment, the material maintains a stable friction coefficient below 0.30 during high-temperature dry friction, demonstrating excellent lubricant slow-release capability and thermal stability.

In order to solve the design and regulation problems of graded porous scaffolds, the triply periodic minimal surface (TPMS) that based on implicit function was taken as the pore unit for constructing the porous scaffolds. And the TPMS structure was controlled by selecting different types of TPMS and defining the distance function. The transition of different structures of TPMS was performed by the weight fusion method. And the dual contouring (DC) algorithm and octree algorithm were used to divide the solid model of the defect bone into hexahedral elements to determine the target assembly spatial. Through the coordinate transformation of the isoparametric element method, the pore units were mapped into the hexahedral elements to construct porous structure. Finally, a Boolean operation was used to obtain a bone scaffold model with porous structure. The examples showed that the gradient model of various irregular pores could be constructed, and the pore size, porosity, and specific surface area of porous scaffolds could be controlled by adjusting the deformation, distribution, volume of the hexahedral elements, and the structure of the TPMS pore units, which provides a feasible method for the design and regulation of heterogeneous porous scaffolds.

Interfacial bonding strength between the substrate and its coating is one of the important indexes affecting the service life of parts. To reduce the manufacturing cost, a mathematical model can be established to quantitatively describe the microscopic surface roughness and its anti-corrosion coating adhesion strength. Anti-corrosion life could be improved by controlling the surface roughness of the substrate. In this study, a model of interfacial bond strength and roughness, which was calibrated using the substrate surface and closely related to the cell spacing and length of the support, was established. Under the same condition as the coating, component materials and the coating thickness, results were obtained that the coating strength changed along with the substrate roughness. When roughness changed between 37.1 μm and 48.4 μm, the bonding strength showed a decreasing trend. The larger the value of the roughness, the more conducive it was to the bonding between the arc spraying layer and the substrate. The adhesion between the coating and substrate was not always increased with the higher roughness on the same surface. It should be evaluated based on the surface roughness and its evaluation parameters, and there was an optimal roughness evaluation and selection range. The experimental results were consistent with the theoretical predictions.