Effect of Cr transition layer on the Al2O3/fe(ceramic/metal) interface microstructure based on binder jetting.

Ceramic coating is a well-established method for enhancing the wear and corrosion resistance of metal components. Al 2 O 3 coating has been extensively utilized in industrial applications. However, existing ceramic coating processes often yield coatings that are relatively thin with limited wear and corrosion resistance. Furthermore, achieving efficient and high-quality coatings on complex metal surfaces poses significant challenges. The poor wettability between ceramics and metals further complicates the bonding at their interface. Chromium (Cr), a commonly used alloying element in steel, exhibits excellent interfacial wettability with iron (Fe), making it an ideal transition material for the Al 2 O 3 /Fe interface. In this study, complex Al 2 O 3 -based ceramic shells were fabricated via Binder Jetting. The Cr coating was coated on the surface of the shell, and then the Fe-based metal liquid was poured into the Al 2 O 3 -based ceramic shell to achieve metallurgical bonding at the Al 2 O 3 /Fe interface by temperature control treatment. The performance of the Al 2 O 3 ceramic matrix and the microstructure of the Al 2 O 3 /Fe interface with the Cr intermediate transition layer were investigated. The results indicate that when the solid loading of the Cr coating is 60 wt%, a uniform, and stable Cr coating can be formed on the surface of the sintered Al 2 O 3 -based ceramic. The bending strength of the Al 2 O 3 -based ceramic matrix increased from 113.79 MPa to 134.69 MPa. The Cr coating significantly improved the wettability between the Al 2 O 3 -based ceramic and the Fe-based metal, reducing the wetting angle from 98.9° to 78.4°. The interface between the Al 2 O 3 -based ceramic and Fe-based metal formed FeCr 2 O 4 after infusion, resulting in a well-bonded interface without significant cracks. [ABSTRACT FROM AUTHOR]