Experimental Investigation on Material Transfer Mechanism in WEDM of Pure Titanium (Grade-2)

Table 3

The analysis of variance for main and interaction effects of parameters on MRR.

Source	SS	DOF	MS	𝐹-value	Prob. > 𝐹	At 95% CI	% Contribution
Model	180.93	8	22.62	97.91	<0.0001	significant
Pulse on time	100.66	1	100.66	435.74	<0.0001	significant	52.61
Pulse off time	41.27	1	41.27	178.64	<0.0001	significant	21.57
Peak current	14.62	1	14.62	63.28	<0.0001	significant	7.64
Spark gap voltage	9.09	1	9.09	39.35	<0.0001	significant	4.75
Pulse off time^2	11.35	1	11.35	49.12	<0.0001	significant	5.93
Peak current^2	0.98	1	0.98	4.24	0.0453	significant	0.512
Pulse off time × peak current	2.26	1	2.26	9.77	0.0031	significant	1.18
Lack of fit	9.40	40	0.24	1.18	0.4750	not significant
𝑅^2=0.9457
𝑅^2 adjusted = 0.9360
Predicted 𝑅^2=0.9228

SS: sum of square, DOF: degree of freedom, MS: mean square, 𝐹-value: Fisher value.