Micromechanical Properties of Zirconia/316L Stainless Steel and Zirconia/17-4PH Stainless Steel Bi-Materials Produced by Two-Component Micro-Powder Injection Molding

The micromechanical behavior of ceramic–metal bi-material products is crucial for their performance in load-bearing applications. The two-component micro-powder injection molding (2C-µPIM) process offers an efficient method to shape ceramic–metal materials. However, joining dissimilar ceramic and metal materials remains challenging due to mismatch in thermal expansion coefficients and sintering shrinkage behavior. Understanding the micromechanical response near the joint interface is therefore essential for improving the joining of dissimilar materials. This understanding supports the optimization of bi-material components for high-reliability applications. This study investigates the micromechanical behavior of bi-materials composed of 3 mol% yttria-stabilized zirconia (3YSZ) with 316L and 17-4PH stainless steels (SS 316L and SS 17-4PH), fabricated using the 2C-µPIM technique. The nanoindentation technique was employed to assess hardness, Young’s modulus, and deformation behavior at the interface. The 3YSZ/SS 316L bi-material exhibited a denser microstructure and higher mechanical properties, including a hardness (2.91 GPa) and modulus (137.42 GPa), compared to 3YSZ/SS 17-4PH, which displayed porosity and lower values (1.19 GPa and 49.21 GPa, respectively). The 3YSZ/SS 17-4PH also showed greater indentation depth and discontinuities, indicating weaker interfacial strength. These results highlight the influence of microstructural characteristics on interfacial mechanics and provide insight to improve ceramic–metal joining via 2C-µPIM.