| dc.description.abstract | This article describes the chips formation during drilling of Ti-6246 titanium alloy using TiAIN
coating carbide insert drill. At the early stage of drilling, the chips had a conical spiral shapes
regardless the parameters used and heat treatment conditions. However, as the depth increases
different types of chips were observed depending on the parameters used. Drilling with high feed
rates, lower cutting speed and with coolant resulted in segmented-type. On the contrary, low feed
rate and high cutting speed result in long-curly chips. Furthermore, when the depth of drilling was
around 10 mm or deeper, a zigzag form of chips was observed regardless the machining
parameters applied. Though the chips fOlIDSwere different, cross sectional observation using
optical microscopy and scanning electron microscopy shows that all the chips had a serrated type.
These chips experienced microstructural elongation at the shear band area. Micro Vickers
hardness tests showed that the hardness of the chips was higher compared to the hardness of the
original material prior to drilling. | en_US |
