Tool life is most affected by

Concept:

Tool life:

• Cutting speed has the greatest influence on tool wear and tool life followed by Feed rate & Depth of cut.
• Most materials can be machined over a wide range of speeds.
• When a shorter tool life is allowable the speed can be increased Relationship between tool life and cutting speed is expressed by the Taylor equation for tool life
• According to Modified Taylor’s equation:

VTnfadb = C

\(T = \frac{{{C^{\frac{1}{n}}}}}{{{V^{\frac{1}{n}}}{f^{\frac{1}{{{n_1}}}}}{d^{\frac{1}{{{n_2}}}}}}}\)

\(\frac{1}{n} > \frac{1}{{{n_1}}} > \frac{1}{{{n_2}}}\)

Where, V = Cutting Speed, T = Tool life, n = a constant based on the tool material. C = a constant based on the tool and the work.

Tool wear and hence tool life of any tool for any work material is governed mainly by the level of the machining parameters i.e., cutting velocity, (VC), feed, (f), and depth of cut (t). 

Cutting velocity affects the maximum and depth of cut minimum.