Development and Optimization of Phenolic Binder–Carbon Black Powder Feedstock for Potential Binder Jet 3D Printing of Carbon Structures
摘要
Carbon structures are widely used in the defense industry, high-temperature tooling and electrochemical energy storage, but their fabrication via traditional methods poses several challenges with complex and intricate geometries. Binder jet 3D printing (BJ3DP) is a versatile technique which offers design freedom to address these challenges, but studies on its potential for printing of carbon structures remain limited. In this research, polymeric binder–carbon black feedstock was developed and optimized for BJ3DP of carbon structures. An aqueous phenolic binder was synthesized and optimized with carbon black powder to meet the properties requisite for the BJ3DP process. To evaluate the powder–binder chemistry, structures were fabricated by manual powder layering and binder spraying approaches to simulate the BJ3DP process and were cured in a heating oven. The results revealed that the optimized binder–powder feedstock was suitable for BJ3DP with a binder shelf life exceeding six months if stored at lower temperatures. The fabricated structures exhibited the maximum density and compressive strength of 0.78 g⋅cm−3 and 1.95 MPa, respectively, for green structures, and 0.95 g⋅cm−3 and 7.2 MPa for cured structures. Furthermore, thermal and spectroscopic studies revealed binder stability, curing behavior and powder–binder interactions. The results demonstrate the suitability of the developed powder–binder feedstock for future BJ3DP of carbon structures which can be used as structural components in defense, electronics and the high-temperature tooling industry after graphitization.