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Mechanical machining is one of the commonly employed techniques in manufacturing
industries, given several other production processes. Due to their high hardness and specific
strength at elevated temperatures, machining of titanium alloys is considered very difficult.
Considering the machinability challenges of these alloys, tool wear and energy consumption
during machining remain the main concern for achieving sustainable machining goals. Since
the tool wear is linked to the product quality and cost of machining, therefore, a comprehensive
wear map approach based on experimental cutting test is very useful for monitoring the tool
life. Whereas energy consumption in a machining process is associated with the machine tool
efficiency, cost of energy and carbon footprints, the evaluation of energy consumption using
energy maps is therefore very helpful in improving machining performances. Thus, improving
the tool life and minimizing energy consumption are the prime contributors in achieving
economic and energy-efficient benefits of production.
The research presented here first studied the tool wear progression in turning of titanium alloy
(Ti6Al4V) and then the effect of progressive tool wear on specific cutting energy was further
analyzed for the development of the energy map. Tool Wear and Specific Cutting Energy maps
were developed for turning of Ti6Al4V alloy by performing a series of unified cutting tests.
The wear map developed plots the wear rate on a feed Vs. cutting speed grid and have identified
regions of low, moderate and high tool wear rates. Interestingly, a high wear zone (avoidance
region) at the interface of low and moderate tool wear appeared on the wear map. Analogous
to the wear map, regions of low, moderate and high energy consumption were also identified
on the energy map. The two maps developed thus corresponds to the cutting conditions
employed in turning operation highlighting high energy and wear regions that should be
avoided during the cutting process. Although wear maps have been presented for a variety of
materials including Ti6Al4V alloys, this research work presents a wear map together with
energy map for turning Ti6Al4V alloy. The energy map plots the Specific Cutting Energy
(SCE) utilized at the tooltip against the cutting condition used in the turning process. The
energy map methodology was used for the selection of optimal cutting condition that will
minimize the energy consumption of the machine tool.
The study of the tool chip contact length and the chip formation analysis is a way to understand
the interactions and mechanics of a machining process. The analysis of the tool’s flank surface
revealed that the chemical interaction between the tool and workpiece is the main cause for
high tool wear and energy consumption as titanium alloys are well known for its severe
ix
reactiveness at higher cutting temperatures. Since machining of titanium alloys is challenging
because of the inherent properties of the material, therefore, this research was focused on the
study of energy consumption and tool wear analysis to achieve economic and sustainable goals
of production engineering. The energy and wear maps thus developed are also very useful on
the shop floor and provide for the choice of cutting conditions to produce parts from Ti6Al4V
alloys, together with less damage to cutting tools and efficient use of machine tools.