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 ZrO2-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 ZrO2-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.