| dc.description.abstract | In drilling process at the industry, the problem that always emerges is severe
wear occurs at cutting tool and poor surface finish on workpiece. This is because of
improper selection of cutting parameters that affect to cutting tool condition. In this
study, the experiment was performed to investigate surface roughness and chip
formation on through hole drilling method using uncoated high speed steel (HSS)
cutting tool in dry machining condition when drilling AISI 1018 mild steel. Surface
roughness was evaluated on workpiece, where to compare surface roughness condition
during the drilling process at various cutting speeds. Meanwhile, the chip formation was
investigated at 8.48 m/min cutting speed. This experiment was conducted using CNC
milling machine with cutting speeds 7.54,8.48, and 9.42 m/min and constant of federate
at 0.15 mm/rev. Besides that, the cutting tools with 6 mm diameter was used and
experiment was stopped when achieved the tool wear criteria of 0.2 mm. Based on
result, value of surface roughness decrease when increase the cutting speed. At speed
8.48 m/min, 24 holes were produced. The lower number of holes produced at highest
speed, 9.42 m/min with 13 holes, while highest number holes produced at lower speed,
7.54 m/min with 29 holes produced. For chip formation, the width of chips for new tool
is greater than worn tool results as well as the thickness of the chip at cutting speed of
7.54 m/min. Therefore, it can be concluded that an increasing of cutting speed will
result in decrease value of surface roughness that give high quality of surface produce. | en_US |
