Laser Machining of AISI 304: An Experimental Study …
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Table 4 Experimental design data and measured values of dross height
Standard
LP (kW)
CS (mm/min)
GP (bar)
Dross height (mm)
1
−1
−1
0
2
2
1
−1
0
1.25
3
−1
1
0
0.95
4
1
1
0
1.7
5
−1
0
−1
2.15
6
1
0
−1
0.85
7
−1
0
1
2
8
1
0
1
1.85
9
0
−1
−1
1.5
10
0
1
−1
1
11
0
−1
1
2.1
12
0
1
1
2.35
13
0
0
0
1.75
14
0
0
0
1.8
15
0
0
0
1.95
16
0
0
0
0.75
17
0
0
0
2.25
3 Results and Discussion
Table 5 shows the analysis of variance (ANOVA) for dross height. Using 95% confidence level analysis is carried out. The significance of model can be verified by
F-value of 26.22. From ANOVA for dross height, it has been identified that cutting
Table 5 Analysis of variance for dross height
Source
Sum of squares df
Mean square F-value p-value
Model terms 4.13
9
0.4593
26.22
0.0001
Significant
A
0.0153
1
0.0153
0.8741
0.0018
B
3.38
1
3.38
192.95
<0.0001
C
0.4753
1
0.4753
27.13
0.0012
B 2
0.2108
1
0.2108
12.03
0.0104
Residual
0.1226
7
0.0175
Lack of fit
0.0856
3
0.0285
3.09
0.1524
Not significant
Pure error
0.0370
4
0.0093
Cor total
4.26
16