Notation
AISI	American Iron & Steel Institute
ANOVA	Analysis of variance
HRC	Hardness measured with the Rockwell test for hard materials
CAM	Computer aided manufacture
RSM	Response surface methodology
BUE	Built up edge
CCD	Central composite design
MRR	Material removal rate
SS	Sum of Squares
MS	Mean Square Symbols
VMS	Vision measuring system
d.f	Degree of freedom
Symbol
str	The trochoidal step means the distance between adjacent centers of revolution path (mm)
vc	Cutting speed (m/min)
vf	Feed rate(mm/min)
Ra	Surface roughness (μm)
Rz	Ten point average height (μm)
Rq	Root-mean-square roughness (μm)
Rsk	skewness
Rku	kurtosis
Rsm	Mean spacing between profile peaks at the mean line
Xi	Estimated output response
xi	Represents the input parameter
d0	Free term of regression equation
di	Coefficients of linear terms
dij	Coefficients of square terms
∈	Experimental error
d1, d2…dn	coefficients of linear terms
X1	Before machining of the tool
X2	After machining of the tool