Abstract:
In this research, the effects of coolant types, cooling techniques, and grinding depth on the
surface properties of the Ti-6Al-4V after surface grinding with white alumina wheel were
investigated. Three coolant types namely sunflower oil, formulated sunflower oil-based emulsions
and soluble cutting oil were applied to the grinding zone using two cooling techniques: wet cooling
and minimum quantity lubrication. The grinding was undertaken at grinding depths of 0.005, 0.010
and 0.015 mm. An L9 orthogonal array was used to design the experiments and undertaken the
evaluation of the variable interrelationships. Surface hardness and surface morphology of the ground
surfaces were determined using Vickers Macro-hardness tester and Zeiss Axio Zoom V16 optical
microscope, respectively.
Results from the signal-to-noise ratio analysis revealed that cooling technique has the most
influence while the grinding depth has the least influence on the surface hardness of ground Ti-6Al-
4V. The optimal parametric setting which gives the highest surface hardness of Ti-6Al-4V was
identified from the main effect plots and were sunflower oil (SO), MQL2 at a flow rate of 0.65 L/h
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AIMS Materials Science Volume 6, Issue 5, 697–712.
and a grinding depth of 0.015 mm. Analysis of variance demonstrated that the individual
contributions of coolant types, cooling techniques and grinding depths to surface hardness were
24.11%, 52.47% and 14.15%, respectively. The morphological investigations established that better
surface finish was achieved through the application of sunflower oil-based emulsions in MQL
cooling technique at a grinding depth of 0.005 mm.
