Binder Jet Printing: A Novel Method for Joining Dissimilar Materials
This invention is a two-step binder jet printing (BJP) and sintering process for creating strong bonds between dissimilar materials, even those with incompatible thermal properties. It enables the full-area surface joining of multi-material components, which results in significantly improved joint strength compared to traditional methods that bond only along edges.
Description
This innovative technique utilizes a two-step binder jet printing process followed by sintering to join dissimilar materials. In the first step, a base layer of a high-melting-point material is created with a designed surface topography. This surface is either textured with "teeth-like" features for mechanical interlocking or is made highly porous using space holders. The base is then sintered, and in the second step, a second material with a lower melting point is printed on top. During this printing, the powder of the second material infiltrates the textured or porous features of the base. Finally, the entire component is sintered again at the lower-melting-point material's sintering temperature. Since the base material remains stable at this temperature, the second material densifies and mechanically interlocks with the base, creating a strong bond without melting the base. This approach avoids the thermal stresses and cracking often seen in conventional thermal-based additive manufacturing methods like Directed Energy Deposition (DED). The process can also incorporate metallurgical alloying if the materials are chemically compatible, further enhancing the joint's strength.Applications
- Energy Storage/Batteries: Can be used for joining materials in high-performance batteries, such as copper and aluminum in lithium-ion batteries.- Biomedical Implants: Ideal for creating multi-material dental implants that combine biocompatible materials like titanium with wear-resistant ceramics.
- Heat Exchangers: Enables the creation of efficient heat exchangers by joining materials with high thermal conductivity (like copper) with corrosion-resistant metals (like stainless steel).
- Hydrogen Storage Systems: Allows the integration of porous materials with high surface areas for hydrogen adsorption with mechanically strong, hydrogen-tight metals.
- Catalytic Components: Can be used to join a structural base with a highly porous, high-surface-area catalytic material for use in gaseous or liquid environments.
Advantages
- Enables Joining of Thermally Mismatched Materials- Superior Joint Strength
- Minimized Thermal Stress
- Combines Porous and Solid Structures