Microstructure Alterations of Ti-6Al-4V ELI during Turning by Using Tungsten Carbide Inserts under Dry Cutting Condition

Ibrahim G.A., Arinal H., . Zulhanif, Haron C.H.C.


Titanium alloys possesses a hexagonal close packed
(h.c.p) structure, called phase to ambient temperature. This
structure changes to body center cubic (b.c.c), called phase to
the temperature of 882 C. Machining process that generates high
temperature during machining can affect on microstructures of
machined surface, which represents as a quality of components.
The turning parameters evaluated are cutting speed (55 - 95
m/min), feed rate (0.15 - 0.35 mm/rev), depth of cut (0.10 - 0.20
mm) and tool grade (uncoated, CVD and PVD). The aims of this
paper are to investigate the effects of machining process on
microstructures of machined surface and chip were machined
using tungsten carbide inserts under dry cutting condition. The
results show that machining at high cutting speed (95 m/min)
affected on the microstructure significantly at the end of
machining. The temperature is the most significant factor
affected on microstructure of the machined surface and chip at
shear zone. The changes of microstructure were also affected by
the tool pressure during cutting.


Ti-6Al-4V ELI; microstructure; alteration; turning; carbide insert

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