| dc.description.abstract | This thesis reports results of experimental and research on dry machining of
Aluminium 6061-T6 using carbide insert cutting tool. The alternative to wet machining
is dry machining (green machining), since there is no used cutting fluid going to
pollute the environment no fog from the cutting fluid that shall endanger the operator
and the chip shall not be contaminated by the cutting fluid The problems on dry
machining including a friction between the surface of working material and the cutting
tool, chip formation mechanism and chip flow and cutting temperature which all
related to the machining parameter and the geometry of cutting tool. The uncoated
carbide cutting tool (ISO KIO) and the coated carbide tool (ISO KIO TiN) are used in
this research and the experiment conducting an incremental design and performed
using CNC TU 2A lathe machine tool. The objective is focused to obtain the
characteristic of the wear mechanism and the failure mode of cutting tool such as the
progression of land wear and crater wear, brittle fracture and tool life. Base on
experimental and reseach results obtained that the failure mode of carbide ISO Kl 0 is
britlle fracture, plastic deformation, flank wear, flaking and excesssive chipping. These
failure modes dominantly on carbide ISO Kl 0 and they are due to the fact that speed of
chip flow is slower than the cutting speed and the radius of chip (Ro) smaller than the
radius chip breaker (R). The chip produce is snarled helix-ribbon with irregularly
entangled and this chip flows curlly up and side with length > 5. 0 cm. The flow
mechanism of this chip begins with laminating the nose cutting tool so that abrasive
wear mechanism is occured and sometimes the chip covers the wear area and it
propagates to flaking and chipping. The maximum flank wear on carbide ISO Kl 0 is at
zone C (0.035 mm). On carbide ISO KIO TiN, there is noflakingfound, and this cutting
tool has lower flank wear (0. 023mm) than ISO Kl 0. This value indicated that ISO Kl 0
TiN 34.29 % better than the performance of ISO KIO. At cutting condition of 300
ml min depth of cut of 0. 8 mm and feed rate of 0. 14 mm/rev shows the worst result for
both cutting tools. From the primer shear angle point of view and the radius of chip
point review, the critical condition that caused the the failure mode of both cutting tools
are at <jJ = 24.68- 33.53 ° and Ro= 0.129- 0.447 mm respectively. From the aspect of
surface roughness using ISO Kl 0 or ISO Kl 0 TiN, it is obtain that the value of Ra
achieved by carbide ISO Kl 0 TiN is better than ISO Kl 0 for all cutting condition tested
The range of surface roughness for ISO KIO is 0.75 -9.27 μm while for ISO KIO TiN
is 0. 63 - 8. 60 μm. These =result are believed due to the capability of TiN layer as a
coolant and a solid lubricant. | en_US |
