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 5

Assessment of the significance of factors.

Mathematical model of the first order without interaction of factors
Coefficients of the mathematical model			Degree of freedom	Sum of squares (SS)	Dispersion S/F	Dispersion ratio FR	Assessment of the significance
Index	Coded	Decoded
0	3.461	6.384	1	239.596	239.596	18,630	Significant
1	0.08913	0.2599983	1	0.127120	0.127120	9.9	Insignificant
2	−0.09804	−0.1708942	1	0.153796	0.153796	12.0	Significant
3	−0.01352	−0.0390300	1	0.002926	0.002926	0.22753	Insignificant
4	0.11003	0.3174936	1	0.193723	0.193723	15.1	Significant
	FR < 10,130 ≥ insignificant				FR > 10,130 ≥ insignificant