Application of response surface methodology for prediction and modeling of surface roughness in ball end milling of OFHC copper

Journal of Materials Science: Materials in Engineering

Table 3 Experimental design-CCD matrix in coded form and measured value of responses

Test no.	Control factors				R _a		% error	R _z		% error
Test no.	f _z	a _p	a _e	v _c	Observed value	Predicted value	% error	Observed value	Predicted value	% error
1	− 1	− 1	− 1	−1	0.290	0.288	0.69	1.820	1.815	0.30
2	1	− 1	− 1	−1	0.380	0.382	− 0.53	2.090	2.117	− 1.30
3	− 1	1	− 1	− 1	0.250	0.251	− 0.40	1.440	1.461	− 1.48
4	1	1	− 1	−1	0.340	0.345	− 1.47	1.780	1.764	0.91
5	− 1	− 1	1	− 1	0.590	0.584	0.99	0.256	2.499	2.39
6	1	− 1	1	−1	0.590	0.591	− 0.14	2.660	2.636	0.89
7	− 1	1	1	− 1	0.520	0.529	− 1.85	2.090	2.145	− 2.65
8	1	1	1	−1	0.550	0.536	2.51	2.250	2.283	− 1.46
9	−1	−1	− 1	1	0.320	0.329	− 3.00	1.830	1.855	− 1.34
10	1	−1	− 1	1	0.390	0.381	2.26	2.150	2.157	− 0.33
11	−1	1	− 1	1	0.290	0.292	− 0.86	1.480	1.501	− 1.43
12	1	1	− 1	1	0.340	0.344	− 1.24	1.790	1.804	− 0.77
13	−1	−1	1	1	0.610	0.603	1.10	2.650	2.689	− 1.46
14	1	−1	1	1	0.570	0.568	0.44	2.860	2.826	1.17
15	−1	1	1	1	0.550	0.549	0.24	2.330	2.335	− 0.23
16	1	1	1	1	0.510	0.513	− 0.57	2.440	2.473	− 1.34
17	−2	0	0	0	0.430	0.426	0.88	2.040	2.007	1.59
18	2	0	0	0	0.480	0.485	− 0.96	2.450	2.447	0.10
19	0	−2	0	0	0.520	0.526	− 1.19	2.620	2.651	− 1.18
20	0	2	0	0	0.440	0.435	1.23	2.010	1.944	3.27
21	0	0	− 2	0	0.170	0.163	4.18	1.290	1.261	2.26
22	0	0	2	0	0.620	0.628	− 1.27	2.620	2.614	0.22
23	0	0	0	− 2	0.430	0.431	− 0.28	2.010	2.013	− 0.12
24	0	0	0	2	0.450	0.447	0.09	2.280	2.242	1.64
25	0	0	0	0	0.700	0.696	0.61	3.670	3.653	0.47
26	0	0	0	0	0.690	0.696	− 0.83	3.640	3.653	− 0.35
27	0	0	0	0	0.690	0.696	− 0.83	3.620	3.653	− 0.91
28	0	0	0	0	0.700	0.696	0.61	3.680	3.653	0.74
29	0	0	0	0	0.690	0.696	− 0.83	3.670	3.653	0.47
30	0	0	0	0	0.700	0.696	0.61	3.660	3.653	0.19
31	0	0	0	0	0.700	0.696	0.61	3.630	3.653	− 0.63