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Nano-sized mullite was synthesized by mechano-chemical, sol-gel/milling, process. Aluminum nitrate and tetraethyl ortho silicate were used as precursors to prepare the single phase gel. The prepared gel was subjected to intense mechanical activation using a planetary ball mill prior to annealing. DTA/TGA results showed that mullitization temperature significantly decreases due to mechanical activation as mullite starts to form at 1094°C in unmilled sample whereas intermediate milling for 20 hours decreases this temperature to 988°C. Also, mullite formation occurs at 1021 and 1003°C for samples milled for 5 and 10 hours, respectively. SEM results showed that the morphology of the products was altered by the intermediate mechanical activation. Calculation of the mullite crystallite sizes indicated that they were indeed in nano scale and this result was confirmed by TEM investigations which shows the mean crystallite size of 70 nm.

In developing a new milling technique that can produce high precision, smoothness, and gloss on nickel workpiece surfaces, a widely used material is in industrial applications, particularly in mold manufacturing, in which the production requires exceptionally high accuracy. In this work, the factors influencing the magnetic material milling process are determined by investigating the distribution of magnetic iron (MIGs) and abrasive grains (AGs) in the working surface of magnetic liquid slurry (MLS). The magnetic liquid slurry (MLS) contained commercially available MIGs successfully applied for milling the surface of magnetic materials with extremely high accuracy. Surface roughness ($\mathrm{\text{Ra}}=0.592$ nm) without leaving scratches on the surface after milling.