Formulae to be remembered for MFMT 201 exam, Manufacturing Processes section.
Cold working flow stress:
where K is the strength
coefficient and n is the strain hardening exponent.
Hot working flow stress:
where C is a strength coefficient and m is the strain rate sensitivity
exponent.
The Taylor tool life equation:
v(T)n = C, where
v is the cutting speed, m/min, T is the tool life, in minutes, C, a constant for a particular tool material,
is the cutting speed for a tool life of 1 minute and n is the Taylor exponent (Do not confuse this use of n with
the cold working index n which is completely different).
Adjusted Specific Cutting Energy:
E = E1(h / href)-a where
E1 is the specific cutting energy,
href = 1 mm and a is between 0.2 and 0.4, 0.3 is used for most materials.
Dr David J Grieve, 2nd March 2009.