vc	Cutting speed (m/min)	vf	Direction of feed motion
ap, DA(CB)	Depth of cut (mm)	A	Yield strength (MPa)
f, CH(DG)	Feed rate (mm/rev)	B	Strain hardening coefficient (MPa)
FEM	Finite element model	C	Strain rate hardening coefficient
F	Cutting force (N)	m	Thermal softening exponent
Fc	Circumferential force (N)	n	Strain hardening exponent
Fr	Radial force (N)	S1	Projection area of chip and rake face contact surfaces on the base plane
Fa	Axial force (N)	S2	Projection area of chip and rake face contact surfaces on the working plane
Pr, ADGE	Base plane	S3	Projection area of chip and rake face contact surfaces on the back plane
Ps,	Cutting plane	T	Temperature (°C)
Po,	Orthogonal plane	Troom	Room temperature (°C)
Pp, ABCD	Back plane	Tmelt	Melting temperature (°C)
Pf, CDGH	Working plane	B 0	Coefficient of temperature and cutting speed term
3D	Three-dimensional
κr	Tool cutting-edge angle (°)	B1~B3	Coefficients of cutting forces, cutting, and tool parameters’ terms
γ0	Rake angle (°)	m1, m2	Exponents of temperature and cutting speed terms
λs	Inclination angle (°)	n1~n6	Exponents of cutting forces, cutting, and tool parameters’ terms
γp, ∠MDA	Back-rake angle (°)	N	Total of simulations (N = 24)
γf, ∠NDG	Side-rake angle (°)	i	The ith simulation (I = 1, 2, ⋯, N.)
R	Correlation coefficient	AARE	Absolute average error
$\overline{\epsilon }$	Equivalent plastic strain	$\overline{\sigma }$	Equivalent plastic stress (MPa)
$\dot{\overline{\epsilon }}$	Equivalent plastic strain rate ($s^{-1}$)	${\dot{\overline{\epsilon }}}_0$	Reference equivalent plastic strain rate ($s^{-1}$)
${\sigma }_{surface}$	Surface residual stress	${\sigma }_c$	Stress component caused by Fc applying to S1
${\sigma }_r$	Stress component caused by Fr applying to S2	${\sigma }_a$	Stress component caused by Fa applying to S3
${\sigma }_T$	Stress component relevant to thermal effect	${\sigma }_{part 1}$	Part of surface residual stress relevant to cutting temperature and cutting speed
${\overline{\sigma }}_{sim}$	Mean of all 24 simulated residual stresses on the surface	${\sigma }_{part 2}$	Part of surface residual stress relevant to cutting force, feed, cutting depth, and tool angle
${\sigma }_{sim}\left(i\right)$	The ith simulated residual stress on the surface	${\sigma }_{pre}\left(i\right)$	The predicted residual stress on the surface for the ith simulation
$f_{GA}$	Optimization objective	${\overline{\sigma }}_{pre}$	Mean of all 24 predicted residual stresses on the surface