Investigation of Oxide Dispersion Strengthening Effect on the Strength of Diffusion‐Bonded AISI304 Parts

In this article, experiments for reinforcing diffusion-bonded AISI304 parts by the oxide dispersion strengthening (ODS) effect (oxide dispersion strengthened) are performed. Small particles, insoluble with temperature, act as obstacles for the dislocation movement. Thin sheet material as a carrier for ceramic particles of different sizes (0.5 and 50 μm, respectively) is used as an interlayer in diffusion bonding experiments. Furthermore, ceramic particles facilitate penetration of stable passivation layers, enabling atomic diffusion across bonding planes. However, a ceramic–metallic interface cannot transfer mechanical load. Hence, the strengthening effect must exceed the weakening of the cross-sectional area caused by the ceramic particles. It is found that an equal distribution of ceramic particles in the interlayer is challenging. Dip coating for 0.5 μm alumina is more suited than a mechanical arrangement of beads several tens of micrometers in size in etched holes or calottes. Samples fail in the interface region due to imperfect inclusion of ceramic particles. It turns out that it is difficult to separate the impact of the smaller grain size of the thin sheet material compared to round stock (Hall–Petch relation) on the one hand from the reinforcing effect from the incorporation of ceramic particles.