Experimental and Statistical Investigation of Machinability of AISI D2 Steel Using Electroerosion Machining Method in Different Machining Parameters

Table 4

Signal/noise values obtained from the experimental study.

Surface roughness (μm)				Hole diameters (mm)				Crater diameters (μm)
Level	Ampere	Time on (μs)	Time off (μs)	Level	Ampere	Time on (μs)	Time off (μs)	Level	Ampere	Time on (μs)	Time off (μs)
1	−9.288	−8.911	−10.947	1	−21.95	−21.92	−21.98	1	−39.65	−39.49	−40.92
2	−11.846	−10.969	−10.521	2	−21.97	−21.96	−21.96	2	−41.78	−40.93	−40.70
3		−11.821	−10.233	3		−21.99	−21.94	3		−41.72	−40.52
Delta	2.558	2.910	0.715	Delta	0.03	0.08	0.04	Delta	2.13	2.23	0.40
Rank	2	1	3	Rank	3	1	2	Rank	2	1	3
Wear amount (g)				Wear rate (g/min)				Processing times (min.)
Level	Ampere	Time on (μs)	Time off (μs)	Level	Ampere	Time on (μs)	Time off (μs)	Level	Ampere	Time on (μs)	Time off (μs)
1	−7.334	−8.301	−6.995	1	−57.55	−51.47	−48.86	1	50.22	43.17	41.87
2	−8.034	−8.706	−7.610	2	−47.73	−54.34	−53.03	2	39.69	45.64	45.42
3		−6.046	−8.447	3		−52.11	−56.03	3		46.06	47.59
Delta	0.700	2.660	1.452	Delta	9.82	2.88	7.17	Delta	10.52	2.90	5.72
Rank	3	1	2	Rank	1	3	2	Rank	1	3	2