Revealing the mechanism of abruptly dropping of the wetting angle for the cast iron and zirconia ceramic system

The wettability behavior and characteristics of the high chromium cast iron (HCCI)/zirconium dioxide system were studied using the sessile drop method. A complete and uniform layer of titanium was prepared on the surface of ZrO₂ ceramics using the salt bath coating method. The introduction of titanium reduced the contact angle of the HCCI/ZrO₂ system abruptly from 110° to approximately 13°, at the solid/liquid interface, no complete layer of reaction products was detected, XRD results indicated that TiO, ZrO, and non-stoichiometric ZrO_2-x were primarily formed at the interface; thereby the spreading of HCCI on the Ti-coated ZrO₂ ceramic plate was primarily dominated by the adsorption of titanium elements at the interface with generation of non-stoichiometric ZrO_2-x, and the diffusion of Fe and Cr elements into the interior of the ceramics. Meanwhile, the introduction of titanium elements at the interface between HCCI and ZrO₂ benefits the preparation of metallurgical well-bonded composite interfaces.