MSc Thesis Defense: Öykü Yanaz, SURFACE STRUCTURING OF ALUMINA DOUGHS THROUGH MICROMACHINING AND IMPRINTING IN THE GREEN STATE, Date & Time: 22 July, 2026 – 1:00 PM, Place: FENS L027
SURFACE STRUCTURING OF ALUMINA DOUGHS THROUGH
MICROMACHINING AND IMPRINTING IN THE GREEN STATE
Öykü Yanaz
Materials Science and Nano Engineering, MSc Thesis, 2026
Thesis Jury
Prof. Özge Akbulut (Thesis Advisor)
Prof. Yusuf Ziya Menceloğlu
Prof. Ozan Aydoğmuş
Date & Time: 22nd of July, 2026 – 1:00 PM
Place: FENS L027
Zoom Link: https://sabanciuniv.zoom.us/j/
Keywords: green-state ceramic machining, surface structuring, imprinting, CNC
micromachining, microfluidic channels
Abstract
Ceramics are widely used in demanding operating conditions due to their high thermal, chemical, and mechanical stability. Micron-scale structuring of ceramic surfaces allows for control of surface properties such as wettability and liquid flow. However, most current methods require multi-step processes, long production times, high costs, and specialized equipment. This study investigates the direct structuring of moldable alumina doughs in the green state, which can be prepared on a benchtop in less than two minutes. Micropit patterns were created by applying molds containing conical microprotrusions to the dough surface with low forces, while microchannels were formed using CNC milling. The morphology, dimensional retention, and manufacturability of the structures after sintering were investigated. The effect of micro-pits on surface wettability was evaluated, and four micromixer geometries were compared in terms of velocity, pressure drop, and concentration distribution. Despite approximately 19.3% linear shrinkage during sintering, the microchannels retained their general shape and could be produced in predictable dimensions. Micro-pit patterns altered the apparent contact angle, and different channel geometries were successfully created using CNC micromachining. Numerical results showed that square wave and curved serpentine channels provided the most homogeneous concentration distributions while generating higher pressure drops. The zigzag channel showed moderate mixing performance, while the straight Y channel exhibited the lowest mixing performance. The results demonstrate that direct structuring of malleable alumina doughs in their green state is an easily applicable approach for creating different surface patterns and microfluidic channel geometries.