Minimization of Surface Roughness and Tool Vibration in CNC Milling Operation

Table 7

Analysis of variance.

Source	Surface roughness ()					Tool life (min.)					Vibration amplitude (mm/sec^2)
	Sum of squares	DOF	Mean square	value	value	Sum of squares	DOF	Mean square	value	value	Sum of squares	DOF	Mean square	value	value
Regression	9.87	9	1.10	2.95	0.0262	50.54	9	5.62	26.38	0.0001	335.53	9	37.28	3.63	0.0107
	0.044	1	0.044	0.12	0.7350	30.45	1	30.45	143.07	0.0001	29.39	1	29.39	2.86	0.1089
	1.64	1	1.64	4.41	0.0511	12.04	1	12.04	56.58	0.0001	117.56	1	117.56	11.45	0.0035
	2.63	1	2.63	7.07	0.0165	4.65	1	4.65	21.85	0.0002	102.72	1	102.72	10.00	0.0057
	0.031	1	0.031	0.083	0.7762	2.33	1	2.33	10.94	0.0042	60.75	1	60.75	5.92	0.0263
	0.69	1	0.69	1.85	0.1920	3.047E − 004	1	3.047E − 004	1.432E − 003	0.9703	8.33	1	8.33	0.81	0.3802
	2.39	1	2.39	6.42	0.0214	0.026	1	0.026	0.12	0.7312	0.000	1	0.000	0.000	1.0000
	1.33	1	1.33	3.57	0.0759	0.63	1	0.63	2.97	0.1028	6.69	1	6.69	0.65	0.4309
	9.335E − 003	1	9.335E − 003	0.025	0.8760	0.10	1	0.10	0.48	0.4993	4.74	1	4.74	0.46	0.5060
	1.12	1	1.12	3.02	0.1006	0.30	1	0.30	1.42	0.2495	5.35	1	5.35	0.52	0.4801
Residual	6.32	17	0.37			3.62	17	0.21			174.55	17	10.27
Total	16.19	26				54.16	26				510.07	26