Mathematical Modeling of the Bearing Ratio Curve Rmr (50% Rz), through Investigation of the Effect of Process Parameters in Hard Turning of Steel C55 (DIN) with Mixed Ceramics MC2 (Al₂O₃ + TiC)

Table 1

Input variables.

No.	Factors	Code	1	0	−1
1	Speed (m/min)	X1	130.00	94.00	64.00
2	Feed (mm/rot)	X2	0.314	0.18	0.1
3	Depth cut (mm)	X3	0.81	0.570	0.39
4	Tool radii (mm)	X4	1.55	1.14	0.85