doiSerbia

Wetting behaviour and reactivity between liquid Gd and ZrO2 substrate

Turalska P. (Foundry Research Institute, Krakow, Poland)
Homa M. (Foundry Research Institute, Krakow, Poland)
Bruzda G. (Foundry Research Institute, Krakow, Poland)
Sobczak N. (Foundry Research Institute, Krakow, Poland + Institute of Precision Mechanics, Warsaw, Poland)
Kaban I. (IFW Dresden, Institute for Complex Materials, Dresden, Germany)
Mattern N. (IFW Dresden, Institute for Complex Materials, Dresden, Germany)
Eckert J. (Erich Schmidt Institute of Materials Science, Austrian Academy of Sciences, Leoben, Austria + Department Materials Physics, Montanuniversitдt Leoben, Leoben, Austria)

The wetting behavior and reactivity between molten pure Gd and polycrystalline 3YSZ substrate (ZrO2 stabilized with 3 wt% of Y2O3)were experimentally determined by a sessile drop method using a classical contact heating coupled with drop pushing procedure. The test was performed under an inert flowing gas atmosphere (Ar) at two temperatures of 1362°C and 1412°C. Immediately after melting (Tm=1341°C), liquid Gd did not wet the substrate forming a contact angle of θ=141°. The non-wetting to wetting transition (θ < 90°) took place after about 110 seconds of interaction and was accompanied by a sudden decrease in the contact angle value to 67°. Further heating of the couple to 1412 °C did not affect wetting (θ=67°±1°). The solidified Gd/3YSZ couple was studied by means of optical microscopy and scanning electron microscopy coupled with X-ray energy dispersive spectroscopy. Structural investigations revealed that the wettability in the Gd/3YSZ system is of a reactive nature associated with the formation of a continuous layer of a wettable reaction product Gd2Zr2O7.

Keywords: Gd, ZrO2, Sessile drop, Wettability, Reactivity, Interfaces